Handle DRQ=1 ERR=1 situation. Revised according to what IDE try_to_flush_leftover_data() does.
Changes:
- For ATA PIO writes and ATAPI devices, just stop the HSM and let EH handle it.
- For ATA PIO reads, read only one block of junk data and then let EH handle it.
Signed-off-by: Albert Lee <albertcc@xxxxxxxxxx>
---
Thanks for the IDE try_to_flush_leftover_data() pointer.
The difference between IDE and irq-pio (before this patch):
1. IDE only does the data transfer for PIO reads.
For PIO writes and ATAPI, it just stops and abort/reset.
2. For PIO reads, only one block of data is transferred. EH then takes over if DRQ is still set after that.
The behavior of irq-pio before this patch is: let HSM go on, until the device set DRQ=0 or all data read.
Te IDE behavior looks safer. (When the device is in bad status, we really should not
write any data to it.)
Patch against irq-pio branch (08a556db919f67e1e4d33ae8d40f7222da34d994).
For your review, thanks.
--- irq-pio0/drivers/scsi/libata-core.c 2006-04-01 10:34:59.000000000 +0800
+++ irq-pio-drq/drivers/scsi/libata-core.c 2006-04-01 17:09:00.000000000 +0800
@@ -3651,13 +3651,16 @@ fsm_start:
/* Device should not ask for data transfer (DRQ=1)
* when it finds something wrong.
- * Anyway, we respect DRQ here and let HSM go on
- * without changing hsm_task_state to HSM_ST_ERR.
+ * We ignore DRQ here and stop the HSM by
+ * changing hsm_task_state to HSM_ST_ERR and
+ * let the EH abort the command or reset the device.
*/
if (unlikely(status & (ATA_ERR | ATA_DF))) {
printk(KERN_WARNING "ata%d: DRQ=1 with device error, dev_stat 0x%X\n",
ap->id, status);
qc->err_mask |= AC_ERR_DEV;
+ ap->hsm_task_state = HSM_ST_ERR;
+ goto fsm_start;
}
/* Send the CDB (atapi) or the first data block (ata pio out).
@@ -3704,13 +3707,16 @@ fsm_start:
/* Device should not ask for data transfer (DRQ=1)
* when it finds something wrong.
- * Anyway, we respect DRQ here and let HSM go on
- * without changing hsm_task_state to HSM_ST_ERR.
+ * We ignore DRQ here and stop the HSM by
+ * changing hsm_task_state to HSM_ST_ERR and
+ * let the EH abort the command or reset the device.
*/
if (unlikely(status & (ATA_ERR | ATA_DF))) {
printk(KERN_WARNING "ata%d: DRQ=1 with device error, dev_stat 0x%X\n",
ap->id, status);
qc->err_mask |= AC_ERR_DEV;
+ ap->hsm_task_state = HSM_ST_ERR;
+ goto fsm_start;
}
atapi_pio_bytes(qc);
@@ -3728,20 +3734,32 @@ fsm_start:
goto fsm_start;
}
- /* Some devices may ask for data transfer (DRQ=1)
- * alone with ERR=1 for PIO reads.
- * We respect DRQ here and let HSM go on without
- * changing hsm_task_state to HSM_ST_ERR.
+ /* For PIO reads, some devices may ask for
+ * data transfer (DRQ=1) alone with ERR=1.
+ * We respect DRQ here and transfer one
+ * block of junk data before changing the
+ * hsm_task_state to HSM_ST_ERR.
+ *
+ * For PIO writes, ERR=1 DRQ=1 doesn't make
+ * sense since the data block has been
+ * transferred to the device.
*/
if (unlikely(status & (ATA_ERR | ATA_DF))) {
- /* For writes, ERR=1 DRQ=1 doesn't make
- * sense since the data block has been
- * transferred to the device.
- */
- WARN_ON(qc->tf.flags & ATA_TFLAG_WRITE);
-
/* data might be corrputed */
qc->err_mask |= AC_ERR_DEV;
+
+ if (!(qc->tf.flags & ATA_TFLAG_WRITE)) {
+ ata_pio_sectors(qc);
+ ata_altstatus(ap);
+ status = ata_wait_idle(ap);
+ }
+
+ /* ata_pio_sectors() might change the
+ * state to HSM_ST_LAST. so, the state
+ * is changed after ata_pio_sectors().
+ */
+ ap->hsm_task_state = HSM_ST_ERR;
+ goto fsm_start;
}
ata_pio_sectors(qc);
-
: send the line "unsubscribe linux-ide" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
