linux/drivers/ide/ide-pm.c
Bartlomiej Zolnierkiewicz 2ea5521022 ide: fix suspend regression
On Monday 12 January 2009, Simon Holm Thøgersen wrote:
> commit 295f000 ("ide: don't execute the next queued command from the
> hard-IRQ context (v2)") breaks suspend to disk for me. On
> 'echo disk > /sys/power/state' the systems hangs, letting me switch
> virtual consoles, but not responding to Alt+SysRq

Restart the request queue early for REQ_TYPE_PM_RESUME requests
(though there is only one resume request for the whole resume
sequence it stays in the queue until is fully completed and now
depends on kblockd for processing consequential resume states).

Reported-and-bisected-by: Simon Holm Thøgersen <odie@cs.aau.dk>
Tested-by: Simon Holm Thøgersen <odie@cs.aau.dk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-01-14 19:19:04 +01:00

240 lines
6.3 KiB
C

#include <linux/kernel.h>
#include <linux/ide.h>
#include <linux/hdreg.h>
int generic_ide_suspend(struct device *dev, pm_message_t mesg)
{
ide_drive_t *drive = dev->driver_data, *pair = ide_get_pair_dev(drive);
ide_hwif_t *hwif = drive->hwif;
struct request *rq;
struct request_pm_state rqpm;
ide_task_t args;
int ret;
/* call ACPI _GTM only once */
if ((drive->dn & 1) == 0 || pair == NULL)
ide_acpi_get_timing(hwif);
memset(&rqpm, 0, sizeof(rqpm));
memset(&args, 0, sizeof(args));
rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
rq->cmd_type = REQ_TYPE_PM_SUSPEND;
rq->special = &args;
rq->data = &rqpm;
rqpm.pm_step = IDE_PM_START_SUSPEND;
if (mesg.event == PM_EVENT_PRETHAW)
mesg.event = PM_EVENT_FREEZE;
rqpm.pm_state = mesg.event;
ret = blk_execute_rq(drive->queue, NULL, rq, 0);
blk_put_request(rq);
/* call ACPI _PS3 only after both devices are suspended */
if (ret == 0 && ((drive->dn & 1) || pair == NULL))
ide_acpi_set_state(hwif, 0);
return ret;
}
int generic_ide_resume(struct device *dev)
{
ide_drive_t *drive = dev->driver_data, *pair = ide_get_pair_dev(drive);
ide_hwif_t *hwif = drive->hwif;
struct request *rq;
struct request_pm_state rqpm;
ide_task_t args;
int err;
/* call ACPI _PS0 / _STM only once */
if ((drive->dn & 1) == 0 || pair == NULL) {
ide_acpi_set_state(hwif, 1);
ide_acpi_push_timing(hwif);
}
ide_acpi_exec_tfs(drive);
memset(&rqpm, 0, sizeof(rqpm));
memset(&args, 0, sizeof(args));
rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
rq->cmd_type = REQ_TYPE_PM_RESUME;
rq->cmd_flags |= REQ_PREEMPT;
rq->special = &args;
rq->data = &rqpm;
rqpm.pm_step = IDE_PM_START_RESUME;
rqpm.pm_state = PM_EVENT_ON;
err = blk_execute_rq(drive->queue, NULL, rq, 1);
blk_put_request(rq);
if (err == 0 && dev->driver) {
struct ide_driver *drv = to_ide_driver(dev->driver);
if (drv->resume)
drv->resume(drive);
}
return err;
}
void ide_complete_power_step(ide_drive_t *drive, struct request *rq)
{
struct request_pm_state *pm = rq->data;
#ifdef DEBUG_PM
printk(KERN_INFO "%s: complete_power_step(step: %d)\n",
drive->name, pm->pm_step);
#endif
if (drive->media != ide_disk)
return;
switch (pm->pm_step) {
case IDE_PM_FLUSH_CACHE: /* Suspend step 1 (flush cache) */
if (pm->pm_state == PM_EVENT_FREEZE)
pm->pm_step = IDE_PM_COMPLETED;
else
pm->pm_step = IDE_PM_STANDBY;
break;
case IDE_PM_STANDBY: /* Suspend step 2 (standby) */
pm->pm_step = IDE_PM_COMPLETED;
break;
case IDE_PM_RESTORE_PIO: /* Resume step 1 (restore PIO) */
pm->pm_step = IDE_PM_IDLE;
break;
case IDE_PM_IDLE: /* Resume step 2 (idle)*/
pm->pm_step = IDE_PM_RESTORE_DMA;
break;
}
}
ide_startstop_t ide_start_power_step(ide_drive_t *drive, struct request *rq)
{
struct request_pm_state *pm = rq->data;
ide_task_t *args = rq->special;
memset(args, 0, sizeof(*args));
switch (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 (ata_id_flush_enabled(drive->id) == 0 ||
(drive->dev_flags & IDE_DFLAG_WCACHE) == 0) {
ide_complete_power_step(drive, rq);
return ide_stopped;
}
if (ata_id_flush_ext_enabled(drive->id))
args->tf.command = ATA_CMD_FLUSH_EXT;
else
args->tf.command = ATA_CMD_FLUSH;
goto out_do_tf;
case IDE_PM_STANDBY: /* Suspend step 2 (standby) */
args->tf.command = ATA_CMD_STANDBYNOW1;
goto out_do_tf;
case IDE_PM_RESTORE_PIO: /* Resume step 1 (restore PIO) */
ide_set_max_pio(drive);
/*
* skip IDE_PM_IDLE for ATAPI devices
*/
if (drive->media != ide_disk)
pm->pm_step = IDE_PM_RESTORE_DMA;
else
ide_complete_power_step(drive, rq);
return ide_stopped;
case IDE_PM_IDLE: /* Resume step 2 (idle) */
args->tf.command = ATA_CMD_IDLEIMMEDIATE;
goto out_do_tf;
case IDE_PM_RESTORE_DMA: /* Resume step 3 (restore DMA) */
/*
* Right now, all we do is call ide_set_dma(drive),
* we could be smarter and check for current xfer_speed
* in struct drive etc...
*/
if (drive->hwif->dma_ops == NULL)
break;
/*
* TODO: respect IDE_DFLAG_USING_DMA
*/
ide_set_dma(drive);
break;
}
pm->pm_step = IDE_PM_COMPLETED;
return ide_stopped;
out_do_tf:
args->tf_flags = IDE_TFLAG_TF | IDE_TFLAG_DEVICE;
args->data_phase = TASKFILE_NO_DATA;
return do_rw_taskfile(drive, args);
}
/**
* ide_complete_pm_request - end the current Power Management request
* @drive: target drive
* @rq: request
*
* This function cleans up the current PM request and stops the queue
* if necessary.
*/
void ide_complete_pm_request(ide_drive_t *drive, struct request *rq)
{
struct request_queue *q = drive->queue;
unsigned long flags;
#ifdef DEBUG_PM
printk("%s: completing PM request, %s\n", drive->name,
blk_pm_suspend_request(rq) ? "suspend" : "resume");
#endif
spin_lock_irqsave(q->queue_lock, flags);
if (blk_pm_suspend_request(rq))
blk_stop_queue(q);
else
drive->dev_flags &= ~IDE_DFLAG_BLOCKED;
spin_unlock_irqrestore(q->queue_lock, flags);
drive->hwif->rq = NULL;
if (blk_end_request(rq, 0, 0))
BUG();
}
void ide_check_pm_state(ide_drive_t *drive, struct request *rq)
{
struct request_pm_state *pm = rq->data;
if (blk_pm_suspend_request(rq) &&
pm->pm_step == IDE_PM_START_SUSPEND)
/* Mark drive blocked when starting the suspend sequence. */
drive->dev_flags |= IDE_DFLAG_BLOCKED;
else if (blk_pm_resume_request(rq) &&
pm->pm_step == IDE_PM_START_RESUME) {
/*
* The first thing we do on wakeup is to wait for BSY bit to
* go away (with a looong timeout) as a drive on this hwif may
* just be POSTing itself.
* We do that before even selecting as the "other" device on
* the bus may be broken enough to walk on our toes at this
* point.
*/
ide_hwif_t *hwif = drive->hwif;
struct request_queue *q = drive->queue;
unsigned long flags;
int rc;
#ifdef DEBUG_PM
printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name);
#endif
rc = ide_wait_not_busy(hwif, 35000);
if (rc)
printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name);
SELECT_DRIVE(drive);
hwif->tp_ops->set_irq(hwif, 1);
rc = ide_wait_not_busy(hwif, 100000);
if (rc)
printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name);
spin_lock_irqsave(q->queue_lock, flags);
blk_start_queue(q);
spin_unlock_irqrestore(q->queue_lock, flags);
}
}