Migrate the sas_ata bridge to use the new libata EH strategy, and
finally implement correct software reset.
WARNING WARNING WARNING! This patch is for experimental use only; it is
nowhere near complete! Especially the sas_ata_freeze() function. This
patch may eat your data and kill your trees.
jgarzik: If an ATA command was in-progress at the time of a port freeze,
can complete after thawing? (Does that even make sense?)
Comments-requested-by: Darrick J. Wong <[email protected]>
---
drivers/scsi/libsas/sas_ata.c | 86 ++++++++++++++++++++++++++++++++++-------
1 files changed, 71 insertions(+), 15 deletions(-)
diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c
index 0829b55..a9925d5 100644
--- a/drivers/scsi/libsas/sas_ata.c
+++ b/drivers/scsi/libsas/sas_ata.c
@@ -35,6 +35,8 @@
#include "../scsi_transport_api.h"
#include <scsi/scsi_eh.h>
+static int sas_issue_ata_srst(struct domain_device *dev);
+
static enum ata_completion_errors sas_to_ata_err(struct task_status_struct *ts)
{
/* Cheesy attempt to translate SAS errors into ATA. Hah! */
@@ -233,37 +235,58 @@ static u8 sas_ata_check_status(struct ata_port *ap)
return dev->sata_dev.tf.command;
}
-static void sas_ata_phy_reset(struct ata_port *ap)
+static void sas_ata_freeze(struct ata_port *ap)
{
- struct domain_device *dev = ap->private_data;
- struct sas_internal *i =
- to_sas_internal(dev->port->ha->core.shost->transportt);
- int res = 0;
+ /* reroute qc_done for all qc's on this port to a dumb free func */
+ /* i wonder if we can get away with throwing out anything that
+ * completes in this time frame, or if we must find the commands
+ * that are in progress and cancel only those? */
+ printk(KERN_ERR "%s: STUB\n", __FUNCTION__);
+}
- if (i->dft->lldd_I_T_nexus_reset)
- res = i->dft->lldd_I_T_nexus_reset(dev);
+static void sas_ata_thaw(struct ata_port *ap)
+{
+ /* empty */
+ printk(KERN_ERR "%s: STUB\n", __FUNCTION__);
+}
- if (res)
- SAS_DPRINTK("%s: Unable to reset I T nexus?\n", __FUNCTION__);
+static int sas_ata_soft_reset(struct ata_link *link, unsigned int *classes,
+ unsigned long deadline)
+{
+ struct ata_port *ap = link->ap;
+ struct domain_device *dev = ap->private_data;
+ int res;
+ /* Send SRST to device */
+ res = sas_issue_ata_srst(dev);
+ printk(KERN_ERR "srst 0 returns %d\n", res);
+
+ /* Set new device type */
switch (dev->sata_dev.command_set) {
case ATA_COMMAND_SET:
SAS_DPRINTK("%s: Found ATA device.\n", __FUNCTION__);
- ap->link.device[0].class = ATA_DEV_ATA;
+ *classes = ATA_DEV_ATA;
break;
case ATAPI_COMMAND_SET:
SAS_DPRINTK("%s: Found ATAPI device.\n", __FUNCTION__);
- ap->link.device[0].class = ATA_DEV_ATAPI;
+ *classes = ATA_DEV_ATAPI;
break;
default:
SAS_DPRINTK("%s: Unknown SATA command set: %d.\n",
__FUNCTION__,
dev->sata_dev.command_set);
- ap->link.device[0].class = ATA_DEV_UNKNOWN;
- break;
+ *classes = ATA_DEV_UNKNOWN;
+ break;
}
- ap->cbl = ATA_CBL_SATA;
+ /* FIXME: What if SRST fails? */
+ return 0;
+}
+
+static void sas_ata_error_handler(struct ata_port *ap)
+{
+ ata_do_eh(ap, NULL, sas_ata_soft_reset, NULL, NULL);
+ //uh... hopefully there's no commands left in here?
}
static void sas_ata_post_internal(struct ata_queued_cmd *qc)
@@ -353,7 +376,9 @@ static struct ata_port_operations sas_sata_ops = {
.check_status = sas_ata_check_status,
.check_altstatus = sas_ata_check_status,
.dev_select = ata_noop_dev_select,
- .phy_reset = sas_ata_phy_reset,
+ .error_handler = sas_ata_error_handler,
+ .freeze = sas_ata_freeze,
+ .thaw = sas_ata_thaw,
.post_internal_cmd = sas_ata_post_internal,
.tf_read = sas_ata_tf_read,
.qc_prep = ata_noop_qc_prep,
@@ -658,6 +683,37 @@ out:
return res;
}
+static int sas_issue_ata_srst(struct domain_device *dev)
+{
+ int res = 0;
+ struct sas_task *task;
+ struct dev_to_host_fis *d2h_fis = (struct dev_to_host_fis *)
+ &dev->frame_rcvd[0];
+
+ res = -ENOMEM;
+ task = sas_alloc_task(GFP_KERNEL);
+ if (!task)
+ goto out;
+
+ task->dev = dev;
+
+ task->ata_task.fis.fis_type = 0x27;
+ /* FIXME: What's a good dummy command? */
+ task->ata_task.fis.command = ATA_CMD_CHK_POWER;
+ task->ata_task.fis.features = 0;
+ task->ata_task.fis.control = ATA_SRST;
+ task->ata_task.fis.device = d2h_fis->device;
+ task->ata_task.retry_count = 1;
+ task->ata_task.device_control_reg_update = 1;
+
+ res = sas_execute_task(task, NULL, 0, DMA_NONE);
+
+ sas_free_task(task);
+out:
+
+ return res;
+}
+
static void sas_sata_propagate_sas_addr(struct domain_device *dev)
{
unsigned long flags;