1 files changed, 121 insertions, 0 deletions

diff --git a/drivers/ide/ide-park.c b/drivers/ide/ide-park.c
new file mode 100644
index 000000000000..03b00e57e93f
--- /dev/null
+++ b/drivers/ide/ide-park.c
@@ -0,0 +1,121 @@
+#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)
+{
+        struct request_queue *q = drive->queue;
+        struct request *rq;
+        int rc;
+
+        timeout += jiffies;
+        spin_lock_irq(&ide_lock);
+        if (drive->dev_flags & IDE_DFLAG_PARKED) {
+                ide_hwgroup_t *hwgroup = drive->hwif->hwgroup;
+                int reset_timer;
+
+                reset_timer = time_before(timeout, drive->sleep);
+                drive->sleep = timeout;
+                wake_up_all(&ide_park_wq);
+                if (reset_timer && hwgroup->sleeping &&
+                    del_timer(&hwgroup->timer)) {
+                        hwgroup->sleeping = 0;
+                        hwgroup->busy = 0;
+                        blk_start_queueing(q);
+                }
+                spin_unlock_irq(&ide_lock);
+                return;
+        }
+        spin_unlock_irq(&ide_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);
+        unsigned long now;
+        unsigned int msecs;
+
+        if (drive->dev_flags & IDE_DFLAG_NO_UNLOAD)
+                return -EOPNOTSUPP;
+
+        spin_lock_irq(&ide_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(&ide_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;
+}