Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff
[linux-2.6.git] / drivers / ide / ide-io.c
index 1984fbe..5748554 100644 (file)
 #include <asm/io.h>
 #include <asm/bitops.h>
 
-static void ide_fill_flush_cmd(ide_drive_t *drive, struct request *rq)
-{
-       char *buf = rq->cmd;
-
-       /*
-        * reuse cdb space for ata command
-        */
-       memset(buf, 0, sizeof(rq->cmd));
-
-       rq->flags |= REQ_DRIVE_TASK | REQ_STARTED;
-       rq->buffer = buf;
-       rq->buffer[0] = WIN_FLUSH_CACHE;
-
-       if (ide_id_has_flush_cache_ext(drive->id) &&
-           (drive->capacity64 >= (1UL << 28)))
-               rq->buffer[0] = WIN_FLUSH_CACHE_EXT;
-}
-
-/*
- * preempt pending requests, and store this cache flush for immediate
- * execution
- */
-static struct request *ide_queue_flush_cmd(ide_drive_t *drive,
-                                          struct request *rq, int post)
-{
-       struct request *flush_rq = &HWGROUP(drive)->wrq;
-
-       /*
-        * write cache disabled, clear the barrier bit and treat it like
-        * an ordinary write
-        */
-       if (!drive->wcache) {
-               rq->flags |= REQ_BAR_PREFLUSH;
-               return rq;
-       }
-
-       ide_init_drive_cmd(flush_rq);
-       ide_fill_flush_cmd(drive, flush_rq);
-
-       flush_rq->special = rq;
-       flush_rq->nr_sectors = rq->nr_sectors;
-
-       if (!post) {
-               drive->doing_barrier = 1;
-               flush_rq->flags |= REQ_BAR_PREFLUSH;
-               blkdev_dequeue_request(rq);
-       } else
-               flush_rq->flags |= REQ_BAR_POSTFLUSH;
-
-       __elv_add_request(drive->queue, flush_rq, ELEVATOR_INSERT_FRONT, 0);
-       HWGROUP(drive)->rq = NULL;
-       return flush_rq;
-}
-
 static int __ide_end_request(ide_drive_t *drive, struct request *rq,
                             int uptodate, int nr_sectors)
 {
@@ -137,15 +83,12 @@ static int __ide_end_request(ide_drive_t *drive, struct request *rq,
 
        if (!end_that_request_first(rq, uptodate, nr_sectors)) {
                add_disk_randomness(rq->rq_disk);
-
-               if (blk_rq_tagged(rq))
-                       blk_queue_end_tag(drive->queue, rq);
-
                blkdev_dequeue_request(rq);
                HWGROUP(drive)->rq = NULL;
-               end_that_request_last(rq);
+               end_that_request_last(rq, uptodate);
                ret = 0;
        }
+
        return ret;
 }
 
@@ -166,29 +109,116 @@ int ide_end_request (ide_drive_t *drive, int uptodate, int nr_sectors)
        unsigned long flags;
        int ret = 1;
 
+       /*
+        * room for locking improvements here, the calls below don't
+        * need the queue lock held at all
+        */
        spin_lock_irqsave(&ide_lock, flags);
        rq = HWGROUP(drive)->rq;
 
        if (!nr_sectors)
                nr_sectors = rq->hard_cur_sectors;
 
-       if (!blk_barrier_rq(rq) || !drive->wcache)
-               ret = __ide_end_request(drive, rq, uptodate, nr_sectors);
-       else {
-               struct request *flush_rq = &HWGROUP(drive)->wrq;
-
-               flush_rq->nr_sectors -= nr_sectors;
-               if (!flush_rq->nr_sectors) {
-                       ide_queue_flush_cmd(drive, rq, 1);
-                       ret = 0;
-               }
-       }
+       ret = __ide_end_request(drive, rq, uptodate, nr_sectors);
 
        spin_unlock_irqrestore(&ide_lock, flags);
        return ret;
 }
 EXPORT_SYMBOL(ide_end_request);
 
+/*
+ * Power Management state machine. This one is rather trivial for now,
+ * we should probably add more, like switching back to PIO on suspend
+ * to help some BIOSes, re-do the door locking on resume, etc...
+ */
+
+enum {
+       ide_pm_flush_cache      = ide_pm_state_start_suspend,
+       idedisk_pm_standby,
+
+       idedisk_pm_idle         = ide_pm_state_start_resume,
+       ide_pm_restore_dma,
+};
+
+static void ide_complete_power_step(ide_drive_t *drive, struct request *rq, u8 stat, u8 error)
+{
+       if (drive->media != ide_disk)
+               return;
+
+       switch (rq->pm->pm_step) {
+       case ide_pm_flush_cache:        /* Suspend step 1 (flush cache) complete */
+               if (rq->pm->pm_state == PM_EVENT_FREEZE)
+                       rq->pm->pm_step = ide_pm_state_completed;
+               else
+                       rq->pm->pm_step = idedisk_pm_standby;
+               break;
+       case idedisk_pm_standby:        /* Suspend step 2 (standby) complete */
+               rq->pm->pm_step = ide_pm_state_completed;
+               break;
+       case idedisk_pm_idle:           /* Resume step 1 (idle) complete */
+               rq->pm->pm_step = ide_pm_restore_dma;
+               break;
+       }
+}
+
+static ide_startstop_t ide_start_power_step(ide_drive_t *drive, struct request *rq)
+{
+       ide_task_t *args = rq->special;
+
+       memset(args, 0, sizeof(*args));
+
+       if (drive->media != ide_disk) {
+               /* skip idedisk_pm_idle for ATAPI devices */
+               if (rq->pm->pm_step == idedisk_pm_idle)
+                       rq->pm->pm_step = ide_pm_restore_dma;
+       }
+
+       switch (rq->pm->pm_step) {
+       case ide_pm_flush_cache:        /* Suspend step 1 (flush cache) */
+               if (drive->media != ide_disk)
+                       break;
+               /* Not supported? Switch to next step now. */
+               if (!drive->wcache || !ide_id_has_flush_cache(drive->id)) {
+                       ide_complete_power_step(drive, rq, 0, 0);
+                       return ide_stopped;
+               }
+               if (ide_id_has_flush_cache_ext(drive->id))
+                       args->tfRegister[IDE_COMMAND_OFFSET] = WIN_FLUSH_CACHE_EXT;
+               else
+                       args->tfRegister[IDE_COMMAND_OFFSET] = WIN_FLUSH_CACHE;
+               args->command_type = IDE_DRIVE_TASK_NO_DATA;
+               args->handler      = &task_no_data_intr;
+               return do_rw_taskfile(drive, args);
+
+       case idedisk_pm_standby:        /* Suspend step 2 (standby) */
+               args->tfRegister[IDE_COMMAND_OFFSET] = WIN_STANDBYNOW1;
+               args->command_type = IDE_DRIVE_TASK_NO_DATA;
+               args->handler      = &task_no_data_intr;
+               return do_rw_taskfile(drive, args);
+
+       case idedisk_pm_idle:           /* Resume step 1 (idle) */
+               args->tfRegister[IDE_COMMAND_OFFSET] = WIN_IDLEIMMEDIATE;
+               args->command_type = IDE_DRIVE_TASK_NO_DATA;
+               args->handler = task_no_data_intr;
+               return do_rw_taskfile(drive, args);
+
+       case ide_pm_restore_dma:        /* Resume step 2 (restore DMA) */
+               /*
+                * Right now, all we do is call hwif->ide_dma_check(drive),
+                * we could be smarter and check for current xfer_speed
+                * in struct drive etc...
+                */
+               if ((drive->id->capability & 1) == 0)
+                       break;
+               if (drive->hwif->ide_dma_check == NULL)
+                       break;
+               drive->hwif->ide_dma_check(drive);
+               break;
+       }
+       rq->pm->pm_step = ide_pm_state_completed;
+       return ide_stopped;
+}
+
 /**
  *     ide_complete_pm_request - end the current Power Management request
  *     @drive: target drive
@@ -214,7 +244,7 @@ static void ide_complete_pm_request (ide_drive_t *drive, struct request *rq)
        }
        blkdev_dequeue_request(rq);
        HWGROUP(drive)->rq = NULL;
-       end_that_request_last(rq);
+       end_that_request_last(rq, 1);
        spin_unlock_irqrestore(&ide_lock, flags);
 }
 
@@ -253,79 +283,6 @@ u64 ide_get_error_location(ide_drive_t *drive, char *args)
 }
 EXPORT_SYMBOL(ide_get_error_location);
 
-static void ide_complete_barrier(ide_drive_t *drive, struct request *rq,
-                                int error)
-{
-       struct request *real_rq = rq->special;
-       int good_sectors, bad_sectors;
-       sector_t sector;
-
-       if (!error) {
-               if (blk_barrier_postflush(rq)) {
-                       /*
-                        * this completes the barrier write
-                        */
-                       __ide_end_request(drive, real_rq, 1, real_rq->hard_nr_sectors);
-                       drive->doing_barrier = 0;
-               } else {
-                       /*
-                        * just indicate that we did the pre flush
-                        */
-                       real_rq->flags |= REQ_BAR_PREFLUSH;
-                       elv_requeue_request(drive->queue, real_rq);
-               }
-               /*
-                * all is fine, return
-                */
-               return;
-       }
-
-       /*
-        * we need to end real_rq, but it's not on the queue currently.
-        * put it back on the queue, so we don't have to special case
-        * anything else for completing it
-        */
-       if (!blk_barrier_postflush(rq))
-               elv_requeue_request(drive->queue, real_rq);
-
-       /*
-        * drive aborted flush command, assume FLUSH_CACHE_* doesn't
-        * work and disable barrier support
-        */
-       if (error & ABRT_ERR) {
-               printk(KERN_ERR "%s: barrier support doesn't work\n", drive->name);
-               __ide_end_request(drive, real_rq, -EOPNOTSUPP, real_rq->hard_nr_sectors);
-               blk_queue_ordered(drive->queue, 0);
-               blk_queue_issue_flush_fn(drive->queue, NULL);
-       } else {
-               /*
-                * find out what part of the request failed
-                */
-               good_sectors = 0;
-               if (blk_barrier_postflush(rq)) {
-                       sector = ide_get_error_location(drive, rq->buffer);
-
-                       if ((sector >= real_rq->hard_sector) &&
-                           (sector < real_rq->hard_sector + real_rq->hard_nr_sectors))
-                               good_sectors = sector - real_rq->hard_sector;
-               } else
-                       sector = real_rq->hard_sector;
-
-               bad_sectors = real_rq->hard_nr_sectors - good_sectors;
-               if (good_sectors)
-                       __ide_end_request(drive, real_rq, 1, good_sectors);
-               if (bad_sectors)
-                       __ide_end_request(drive, real_rq, 0, bad_sectors);
-
-               printk(KERN_ERR "%s: failed barrier write: "
-                               "sector=%Lx(good=%d/bad=%d)\n",
-                               drive->name, (unsigned long long)sector,
-                               good_sectors, bad_sectors);
-       }
-
-       drive->doing_barrier = 0;
-}
-
 /**
  *     ide_end_drive_cmd       -       end an explicit drive command
  *     @drive: command 
@@ -409,7 +366,7 @@ void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err)
                printk("%s: complete_power_step(step: %d, stat: %x, err: %x)\n",
                        drive->name, rq->pm->pm_step, stat, err);
 #endif
-               DRIVER(drive)->complete_power_step(drive, rq, stat, err);
+               ide_complete_power_step(drive, rq, stat, err);
                if (rq->pm->pm_step == ide_pm_state_completed)
                        ide_complete_pm_request(drive, rq);
                return;
@@ -417,12 +374,9 @@ void ide_end_drive_cmd (ide_drive_t *drive, u8 stat, u8 err)
 
        spin_lock_irqsave(&ide_lock, flags);
        blkdev_dequeue_request(rq);
-
-       if (blk_barrier_preflush(rq) || blk_barrier_postflush(rq))
-               ide_complete_barrier(drive, rq, err);
-
        HWGROUP(drive)->rq = NULL;
-       end_that_request_last(rq);
+       rq->errors = err;
+       end_that_request_last(rq, !rq->errors);
        spin_unlock_irqrestore(&ide_lock, flags);
 }
 
@@ -453,6 +407,17 @@ static void try_to_flush_leftover_data (ide_drive_t *drive)
        }
 }
 
+static void ide_kill_rq(ide_drive_t *drive, struct request *rq)
+{
+       if (rq->rq_disk) {
+               ide_driver_t *drv;
+
+               drv = *(ide_driver_t **)rq->rq_disk->private_data;
+               drv->end_request(drive, 0, 0);
+       } else
+               ide_end_request(drive, 0, 0);
+}
+
 static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
 {
        ide_hwif_t *hwif = drive->hwif;
@@ -487,7 +452,7 @@ static ide_startstop_t ide_ata_error(ide_drive_t *drive, struct request *rq, u8
                hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG);
 
        if (rq->errors >= ERROR_MAX || blk_noretry_request(rq))
-               drive->driver->end_request(drive, 0, 0);
+               ide_kill_rq(drive, rq);
        else {
                if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
                        ++rq->errors;
@@ -516,7 +481,7 @@ static ide_startstop_t ide_atapi_error(ide_drive_t *drive, struct request *rq, u
                hwif->OUTB(WIN_IDLEIMMEDIATE, IDE_COMMAND_REG);
 
        if (rq->errors >= ERROR_MAX) {
-               drive->driver->end_request(drive, 0, 0);
+               ide_kill_rq(drive, rq);
        } else {
                if ((rq->errors & ERROR_RESET) == ERROR_RESET) {
                        ++rq->errors;
@@ -536,6 +501,8 @@ __ide_error(ide_drive_t *drive, struct request *rq, u8 stat, u8 err)
        return ide_atapi_error(drive, rq, stat, err);
 }
 
+EXPORT_SYMBOL_GPL(__ide_error);
+
 /**
  *     ide_error       -       handle an error on the IDE
  *     @drive: drive the error occurred on
@@ -566,7 +533,13 @@ ide_startstop_t ide_error (ide_drive_t *drive, const char *msg, u8 stat)
                return ide_stopped;
        }
 
-       return drive->driver->error(drive, rq, stat, err);
+       if (rq->rq_disk) {
+               ide_driver_t *drv;
+
+               drv = *(ide_driver_t **)rq->rq_disk->private_data;
+               return drv->error(drive, rq, stat, err);
+       } else
+               return __ide_error(drive, rq, stat, err);
 }
 
 EXPORT_SYMBOL_GPL(ide_error);
@@ -576,12 +549,15 @@ ide_startstop_t __ide_abort(ide_drive_t *drive, struct request *rq)
        if (drive->media != ide_disk)
                rq->errors |= ERROR_RESET;
 
-       DRIVER(drive)->end_request(drive, 0, 0);
+       ide_kill_rq(drive, rq);
+
        return ide_stopped;
 }
 
+EXPORT_SYMBOL_GPL(__ide_abort);
+
 /**
- *     ide_abort       -       abort pending IDE operatins
+ *     ide_abort       -       abort pending IDE operations
  *     @drive: drive the error occurred on
  *     @msg: message to report
  *
@@ -608,7 +584,13 @@ ide_startstop_t ide_abort(ide_drive_t *drive, const char *msg)
                return ide_stopped;
        }
 
-       return drive->driver->abort(drive, rq);
+       if (rq->rq_disk) {
+               ide_driver_t *drv;
+
+               drv = *(ide_driver_t **)rq->rq_disk->private_data;
+               return drv->abort(drive, rq);
+       } else
+               return __ide_abort(drive, rq);
 }
 
 /**
@@ -638,7 +620,7 @@ static void ide_cmd (ide_drive_t *drive, u8 cmd, u8 nsect,
  *     @drive: drive the completion interrupt occurred on
  *
  *     drive_cmd_intr() is invoked on completion of a special DRIVE_CMD.
- *     We do any necessary daya reading and then wait for the drive to
+ *     We do any necessary data reading and then wait for the drive to
  *     go non busy. At that point we may read the error data and complete
  *     the request
  */
@@ -661,13 +643,72 @@ static ide_startstop_t drive_cmd_intr (ide_drive_t *drive)
                        udelay(100);
        }
 
-       if (!OK_STAT(stat, READY_STAT, BAD_STAT) && DRIVER(drive) != NULL)
+       if (!OK_STAT(stat, READY_STAT, BAD_STAT))
                return ide_error(drive, "drive_cmd", stat);
                /* calls ide_end_drive_cmd */
        ide_end_drive_cmd(drive, stat, hwif->INB(IDE_ERROR_REG));
        return ide_stopped;
 }
 
+static void ide_init_specify_cmd(ide_drive_t *drive, ide_task_t *task)
+{
+       task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect;
+       task->tfRegister[IDE_SECTOR_OFFSET]  = drive->sect;
+       task->tfRegister[IDE_LCYL_OFFSET]    = drive->cyl;
+       task->tfRegister[IDE_HCYL_OFFSET]    = drive->cyl>>8;
+       task->tfRegister[IDE_SELECT_OFFSET]  = ((drive->head-1)|drive->select.all)&0xBF;
+       task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SPECIFY;
+
+       task->handler = &set_geometry_intr;
+}
+
+static void ide_init_restore_cmd(ide_drive_t *drive, ide_task_t *task)
+{
+       task->tfRegister[IDE_NSECTOR_OFFSET] = drive->sect;
+       task->tfRegister[IDE_COMMAND_OFFSET] = WIN_RESTORE;
+
+       task->handler = &recal_intr;
+}
+
+static void ide_init_setmult_cmd(ide_drive_t *drive, ide_task_t *task)
+{
+       task->tfRegister[IDE_NSECTOR_OFFSET] = drive->mult_req;
+       task->tfRegister[IDE_COMMAND_OFFSET] = WIN_SETMULT;
+
+       task->handler = &set_multmode_intr;
+}
+
+static ide_startstop_t ide_disk_special(ide_drive_t *drive)
+{
+       special_t *s = &drive->special;
+       ide_task_t args;
+
+       memset(&args, 0, sizeof(ide_task_t));
+       args.command_type = IDE_DRIVE_TASK_NO_DATA;
+
+       if (s->b.set_geometry) {
+               s->b.set_geometry = 0;
+               ide_init_specify_cmd(drive, &args);
+       } else if (s->b.recalibrate) {
+               s->b.recalibrate = 0;
+               ide_init_restore_cmd(drive, &args);
+       } else if (s->b.set_multmode) {
+               s->b.set_multmode = 0;
+               if (drive->mult_req > drive->id->max_multsect)
+                       drive->mult_req = drive->id->max_multsect;
+               ide_init_setmult_cmd(drive, &args);
+       } else if (s->all) {
+               int special = s->all;
+               s->all = 0;
+               printk(KERN_ERR "%s: bad special flag: 0x%02x\n", drive->name, special);
+               return ide_stopped;
+       }
+
+       do_rw_taskfile(drive, &args);
+
+       return ide_started;
+}
+
 /**
  *     do_special              -       issue some special commands
  *     @drive: drive the command is for
@@ -689,9 +730,14 @@ static ide_startstop_t do_special (ide_drive_t *drive)
                if (HWIF(drive)->tuneproc != NULL)
                        HWIF(drive)->tuneproc(drive, drive->tune_req);
                return ide_stopped;
+       } else {
+               if (drive->media == ide_disk)
+                       return ide_disk_special(drive);
+
+               s->all = 0;
+               drive->mult_req = 0;
+               return ide_stopped;
        }
-       else
-               return DRIVER(drive)->special(drive);
 }
 
 void ide_map_sg(ide_drive_t *drive, struct request *rq)
@@ -724,7 +770,7 @@ EXPORT_SYMBOL_GPL(ide_init_sg_cmd);
 
 /**
  *     execute_drive_command   -       issue special drive command
- *     @drive: the drive to issue th command on
+ *     @drive: the drive to issue the command on
  *     @rq: the request structure holding the command
  *
  *     execute_drive_cmd() issues a special drive command,  usually 
@@ -886,7 +932,7 @@ static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq)
                        printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name);
                SELECT_DRIVE(drive);
                HWIF(drive)->OUTB(8, HWIF(drive)->io_ports[IDE_CONTROL_OFFSET]);
-               rc = ide_wait_not_busy(HWIF(drive), 10000);
+               rc = ide_wait_not_busy(HWIF(drive), 100000);
                if (rc)
                        printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name);
        }
@@ -897,6 +943,8 @@ static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq)
                return startstop;
        }
        if (!drive->special.all) {
+               ide_driver_t *drv;
+
                if (rq->flags & (REQ_DRIVE_CMD | REQ_DRIVE_TASK))
                        return execute_drive_cmd(drive, rq);
                else if (rq->flags & REQ_DRIVE_TASKFILE)
@@ -906,17 +954,19 @@ static ide_startstop_t start_request (ide_drive_t *drive, struct request *rq)
                        printk("%s: start_power_step(step: %d)\n",
                                drive->name, rq->pm->pm_step);
 #endif
-                       startstop = DRIVER(drive)->start_power_step(drive, rq);
+                       startstop = ide_start_power_step(drive, rq);
                        if (startstop == ide_stopped &&
                            rq->pm->pm_step == ide_pm_state_completed)
                                ide_complete_pm_request(drive, rq);
                        return startstop;
                }
-               return (DRIVER(drive)->do_request(drive, rq, block));
+
+               drv = *(ide_driver_t **)rq->rq_disk->private_data;
+               return drv->do_request(drive, rq, block);
        }
        return do_special(drive);
 kill_rq:
-       DRIVER(drive)->end_request(drive, 0, 0);
+       ide_kill_rq(drive, rq);
        return ide_stopped;
 }
 
@@ -963,7 +1013,7 @@ repeat:
         * though that is 3 requests, it must be seen as a single transaction.
         * we must not preempt this drive until that is complete
         */
-       if (drive->doing_barrier) {
+       if (blk_queue_flushing(drive->queue)) {
                /*
                 * small race where queue could get replugged during
                 * the 3-request flush cycle, just yank the plug since
@@ -1048,6 +1098,7 @@ static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq)
        ide_hwif_t      *hwif;
        struct request  *rq;
        ide_startstop_t startstop;
+       int             loops = 0;
 
        /* for atari only: POSSIBLY BROKEN HERE(?) */
        ide_get_lock(ide_intr, hwgroup);
@@ -1100,6 +1151,7 @@ static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq)
                        /* no more work for this hwgroup (for now) */
                        return;
                }
+       again:
                hwif = HWIF(drive);
                if (hwgroup->hwif->sharing_irq &&
                    hwif != hwgroup->hwif &&
@@ -1127,13 +1179,6 @@ static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq)
                        break;
                }
 
-               /*
-                * if rq is a barrier write, issue pre cache flush if not
-                * already done
-                */
-               if (blk_barrier_rq(rq) && !blk_barrier_preflush(rq))
-                       rq = ide_queue_flush_cmd(drive, rq, 0);
-
                /*
                 * Sanity: don't accept a request that isn't a PM request
                 * if we are currently power managed. This is very important as
@@ -1146,8 +1191,14 @@ static void ide_do_request (ide_hwgroup_t *hwgroup, int masked_irq)
                 * though. I hope that doesn't happen too much, hopefully not
                 * unless the subdriver triggers such a thing in its own PM
                 * state machine.
+                *
+                * We count how many times we loop here to make sure we service
+                * all drives in the hwgroup without looping for ever
                 */
                if (drive->blocked && !blk_pm_request(rq) && !(rq->flags & REQ_PREEMPT)) {
+                       drive = drive->next ? drive->next : hwgroup->drive;
+                       if (loops++ < 4 && !blk_queue_plugged(drive->queue))
+                               goto again;
                        /* We clear busy, there should be no pending ATA command at this point. */
                        hwgroup->busy = 0;
                        break;
@@ -1575,12 +1626,6 @@ EXPORT_SYMBOL(ide_init_drive_cmd);
  *     for the new rq to be completed.  This is VERY DANGEROUS, and is
  *     intended for careful use by the ATAPI tape/cdrom driver code.
  *
- *     If action is ide_next, then the rq is queued immediately after
- *     the currently-being-processed-request (if any), and the function
- *     returns without waiting for the new rq to be completed.  As above,
- *     This is VERY DANGEROUS, and is intended for careful use by the
- *     ATAPI tape/cdrom driver code.
- *
  *     If action is ide_end, then the rq is queued at the end of the
  *     request queue, and the function returns immediately without waiting
  *     for the new rq to be completed. This is again intended for careful
@@ -1598,8 +1643,6 @@ int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t actio
        rq->errors = 0;
        rq->rq_status = RQ_ACTIVE;
 
-       rq->rq_disk = drive->disk;
-
        /*
         * we need to hold an extra reference to request for safe inspection
         * after completion
@@ -1607,6 +1650,7 @@ int ide_do_drive_cmd (ide_drive_t *drive, struct request *rq, ide_action_t actio
        if (must_wait) {
                rq->ref_count++;
                rq->waiting = &wait;
+               rq->end_io = blk_end_sync_rq;
        }
 
        spin_lock_irqsave(&ide_lock, flags);