[SCSI] libsas: execute transport link resets with libata-eh via host workqueue

[mirror_ubuntu-bionic-kernel.git] / drivers / scsi / libsas / sas_init.c

diff --git a/drivers/scsi/libsas/sas_init.c b/drivers/scsi/libsas/sas_init.c
index cb65adf4ab16790f5b8a8377cbcee1e8d26e31e1..a15fb861daba4ac1975add39c9891739761fb938 100644 (file)
--- a/drivers/scsi/libsas/sas_init.c
+++ b/drivers/scsi/libsas/sas_init.c
@@ -28,6 +28,7 @@
 #include <linux/init.h>
 #include <linux/device.h>
 #include <linux/spinlock.h>
+#include <scsi/sas_ata.h>
 #include <scsi/scsi_host.h>
 #include <scsi/scsi_device.h>
 #include <scsi/scsi_transport.h>
@@ -195,6 +196,59 @@ static int sas_get_linkerrors(struct sas_phy *phy)
        return sas_smp_get_phy_events(phy);
 }
 
+/**
+ * transport_sas_phy_reset - reset a phy and permit libata to manage the link
+ *
+ * phy reset request via sysfs in host workqueue context so we know we
+ * can block on eh and safely traverse the domain_device topology
+ */
+static int transport_sas_phy_reset(struct sas_phy *phy, int hard_reset)
+{
+       int ret;
+       enum phy_func reset_type;
+
+       if (hard_reset)
+               reset_type = PHY_FUNC_HARD_RESET;
+       else
+               reset_type = PHY_FUNC_LINK_RESET;
+
+       if (scsi_is_sas_phy_local(phy)) {
+               struct Scsi_Host *shost = dev_to_shost(phy->dev.parent);
+               struct sas_ha_struct *sas_ha = SHOST_TO_SAS_HA(shost);
+               struct asd_sas_phy *asd_phy = sas_ha->sas_phy[phy->number];
+               struct sas_internal *i =
+                       to_sas_internal(sas_ha->core.shost->transportt);
+               struct domain_device *dev = NULL;
+
+               if (asd_phy->port)
+                       dev = asd_phy->port->port_dev;
+
+               /* validate that dev has been probed */
+               if (dev)
+                       dev = sas_find_dev_by_rphy(dev->rphy);
+
+               if (dev && dev_is_sata(dev) && !hard_reset) {
+                       sas_ata_schedule_reset(dev);
+                       sas_ata_wait_eh(dev);
+                       ret = 0;
+               } else
+                       ret = i->dft->lldd_control_phy(asd_phy, reset_type, NULL);
+       } else {
+               struct sas_rphy *rphy = dev_to_rphy(phy->dev.parent);
+               struct domain_device *ddev = sas_find_dev_by_rphy(rphy);
+               struct domain_device *ata_dev = sas_ex_to_ata(ddev, phy->number);
+
+               if (ata_dev && !hard_reset) {
+                       sas_ata_schedule_reset(ata_dev);
+                       sas_ata_wait_eh(ata_dev);
+                       ret = 0;
+               } else
+                       ret = sas_smp_phy_control(ddev, phy->number, reset_type, NULL);
+       }
+
+       return ret;
+}
+
 int sas_phy_enable(struct sas_phy *phy, int enable)
 {
        int ret;
@@ -300,7 +354,7 @@ static void phy_reset_work(struct work_struct *work)
 {
        struct sas_phy_data *d = container_of(work, typeof(*d), reset_work);
 
-       d->reset_result = sas_phy_reset(d->phy, d->hard_reset);
+       d->reset_result = transport_sas_phy_reset(d->phy, d->hard_reset);
 }
 
 static int sas_phy_setup(struct sas_phy *phy)