IDE: Fix HDIO_DRIVE_RESET handling

Currently, the code path executing an HDIO_DRIVE_RESET ioctl is broken
in various ways.  Most importantly, it is treated as an out of band
request in an illegal way which may very likely lead to system lock ups.
Use the drive's request queue to avoid this problem (and fix a locking
issue for free along the way).

Signed-off-by: Elias Oltmanns <eo@nebensachen.de>
Cc: "Alan Cox" <alan@lxorguk.ukuu.org.uk>
Cc: "Randy Dunlap" <randy.dunlap@oracle.com>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

1 files changed, 13 insertions, 5 deletions

diff --git a/drivers/ide/ide-iops.c b/drivers/ide/ide-iops.c
index 80ad4f234f3f..96f63eb12092 100644
--- a/drivers/ide/ide-iops.c
+++ b/drivers/ide/ide-iops.c
@@ -905,6 +905,14 @@ void ide_execute_pkt_cmd(ide_drive_t *drive)
 }
 EXPORT_SYMBOL_GPL(ide_execute_pkt_cmd);
 
+static inline void ide_complete_drive_reset(ide_drive_t *drive)
+{
+        struct request *rq = drive->hwif->hwgroup->rq;
+
+        if (rq && blk_special_request(rq) && rq->cmd[0] == REQ_DRIVE_RESET)
+                ide_end_request(drive, 1, 0);
+}
+
 /* needed below */
 static ide_startstop_t do_reset1 (ide_drive_t *, int);
 
@@ -940,7 +948,7 @@ static ide_startstop_t atapi_reset_pollfunc (ide_drive_t *drive)
         }
         /* done polling */
         hwgroup->polling = 0;
-        hwgroup->resetting = 0;
+        ide_complete_drive_reset(drive);
         return ide_stopped;
 }
 
@@ -961,7 +969,7 @@ static ide_startstop_t reset_pollfunc (ide_drive_t *drive)
                 if (port_ops->reset_poll(drive)) {
                         printk(KERN_ERR "%s: host reset_poll failure for %s.\n",
                                 hwif->name, drive->name);
-                        return ide_stopped;
+                        goto out;
                 }
         }
 
@@ -1004,7 +1012,8 @@ static ide_startstop_t reset_pollfunc (ide_drive_t *drive)
                 }
         }
         hwgroup->polling = 0;   /* done polling */
-        hwgroup->resetting = 0; /* done reset attempt */
+out:
+        ide_complete_drive_reset(drive);
         return ide_stopped;
 }
 
@@ -1090,7 +1099,6 @@ static ide_startstop_t do_reset1 (ide_drive_t *drive, int do_not_try_atapi)
 
         /* For an ATAPI device, first try an ATAPI SRST. */
         if (drive->media != ide_disk && !do_not_try_atapi) {
-                hwgroup->resetting = 1;
                 pre_reset(drive);
                 SELECT_DRIVE(drive);
                 udelay (20);
@@ -1112,10 +1120,10 @@ static ide_startstop_t do_reset1 (ide_drive_t *drive, int do_not_try_atapi)
 
         if (io_ports->ctl_addr == 0) {
                 spin_unlock_irqrestore(&ide_lock, flags);
+                ide_complete_drive_reset(drive);
                 return ide_stopped;
         }
 
-        hwgroup->resetting = 1;
         /*
          * Note that we also set nIEN while resetting the device,
          * to mask unwanted interrupts from the interface during the reset.