xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

[SCSI] libata, libsas: introduce sched_eh and end_eh port ops

Browse Source 
When managing shost->host_eh_scheduled libata assumes that there is a
1:1 shost-to-ata_port relationship.  libsas creates a 1:N relationship
so it needs to manage host_eh_scheduled cumulatively at the host level.
The sched_eh and end_eh port port ops allow libsas to track when domain
devices enter/leave the "eh-pending" state under ha->lock (previously
named ha->state_lock, but it is no longer just a lock for ha->state
changes).

Since host_eh_scheduled indicates eh without backing commands pinning
the device it can be deallocated at any time.  Move the taking of the
domain_device reference under the port_lock to guarantee that the
ata_port stays around for the duration of eh.

Reviewed-by: Jacek Danecki <jacek.danecki@intel.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This commit is contained in:
Dan Williams
2012-06-21 23:25:27 -07:00
committed by James Bottomley
parent 3b661a92e8
commit e4a9c3732c
10 changed files with 136 additions and 39 deletions
Download Patch File Download Diff File Expand all files Collapse all files

61
drivers/ata/libata-eh.c
View File

@@ -793,12 +793,12 @@ void ata_scsi_port_error_handler(struct Scsi_Host *host, struct ata_port *ap)
ata_for_each_link(link, ap, HOST_FIRST)
memset(&link->eh_info, 0, sizeof(link->eh_info));
/* Clear host_eh_scheduled while holding ap->lock such
* that if exception occurs after this point but
* before EH completion, SCSI midlayer will
/* end eh (clear host_eh_scheduled) while holding
* ap->lock such that if exception occurs after this
* point but before EH completion, SCSI midlayer will
* re-initiate EH.
*/
host->host_eh_scheduled = 0;
ap->ops->end_eh(ap);
spin_unlock_irqrestore(ap->lock, flags);
ata_eh_release(ap);
@@ -985,6 +985,48 @@ void ata_qc_schedule_eh(struct ata_queued_cmd *qc)
spin_unlock_irqrestore(q->queue_lock, flags);
}
/**
* ata_std_sched_eh - non-libsas ata_ports issue eh with this common routine
* @ap: ATA port to schedule EH for
*
* LOCKING: inherited from ata_port_schedule_eh
* spin_lock_irqsave(host lock)
*/
void ata_std_sched_eh(struct ata_port *ap)
{
WARN_ON(!ap->ops->error_handler);
if (ap->pflags & ATA_PFLAG_INITIALIZING)
return;
ata_eh_set_pending(ap, 1);
scsi_schedule_eh(ap->scsi_host);
DPRINTK("port EH scheduled\n");
}
EXPORT_SYMBOL_GPL(ata_std_sched_eh);
/**
* ata_std_end_eh - non-libsas ata_ports complete eh with this common routine
* @ap: ATA port to end EH for
*
* In the libata object model there is a 1:1 mapping of ata_port to
* shost, so host fields can be directly manipulated under ap->lock, in
* the libsas case we need to hold a lock at the ha->level to coordinate
* these events.
*
* LOCKING:
* spin_lock_irqsave(host lock)
*/
void ata_std_end_eh(struct ata_port *ap)
{
struct Scsi_Host *host = ap->scsi_host;
host->host_eh_scheduled = 0;
}
EXPORT_SYMBOL(ata_std_end_eh);
/**
* ata_port_schedule_eh - schedule error handling without a qc
* @ap: ATA port to schedule EH for
@@ -997,15 +1039,8 @@ void ata_qc_schedule_eh(struct ata_queued_cmd *qc)
*/
void ata_port_schedule_eh(struct ata_port *ap)
{
WARN_ON(!ap->ops->error_handler);
if (ap->pflags & ATA_PFLAG_INITIALIZING)
return;
ata_eh_set_pending(ap, 1);
scsi_schedule_eh(ap->scsi_host);
DPRINTK("port EH scheduled\n");
/* see: ata_std_sched_eh, unless you know better */
ap->ops->sched_eh(ap);
}
static int ata_do_link_abort(struct ata_port *ap, struct ata_link *link)