[SCSI] libsas: enforce eh strategy handlers only in eh context

The strategy handlers may be called in places that are problematic for
libsas (i.e. sata resets outside of domain revalidation filtering /
libata link recovery), or problematic for userspace (non-blocking ioctl
to sleeping reset functions).  However, these routines are also called
for eh escalations and recovery of scsi_eh_prep_cmnd(), so permit them
as long as we are running in the host's error handler, otherwise arrange
for them to be triggered in eh_context.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/scsi/libsas/sas_init.c b/drivers/scsi/libsas/sas_init.c
index 6909fefa32c5..1bbab3d94a20 100644
--- a/drivers/scsi/libsas/sas_init.c
+++ b/drivers/scsi/libsas/sas_init.c
@@ -116,7 +116,9 @@ int sas_register_ha(struct sas_ha_struct *sas_ha)
         set_bit(SAS_HA_REGISTERED, &sas_ha->state);
         spin_lock_init(&sas_ha->lock);
         mutex_init(&sas_ha->drain_mutex);
+        init_waitqueue_head(&sas_ha->eh_wait_q);
         INIT_LIST_HEAD(&sas_ha->defer_q);
+        INIT_LIST_HEAD(&sas_ha->eh_dev_q);
 
         error = sas_register_phys(sas_ha);
         if (error) {