[SCSI] fix oops on usb storage device disconnect

We fix the oops by enforcing the host state model.  There have also
been two extra states added: SHOST_CANCEL_RECOVERY and
SHOST_DEL_RECOVERY so we can take the model through host removal while
the recovery thread is active.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
This commit is contained in:
James Bottomley
2005-09-18 15:05:20 -05:00
committed by James Bottomley
parent a64358db12
commit 939647ee30
8 changed files with 66 additions and 16 deletions

View File

@@ -98,6 +98,7 @@ int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state)
switch (oldstate) {
case SHOST_CREATED:
case SHOST_RUNNING:
case SHOST_CANCEL_RECOVERY:
break;
default:
goto illegal;
@@ -107,12 +108,31 @@ int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state)
case SHOST_DEL:
switch (oldstate) {
case SHOST_CANCEL:
case SHOST_DEL_RECOVERY:
break;
default:
goto illegal;
}
break;
case SHOST_CANCEL_RECOVERY:
switch (oldstate) {
case SHOST_CANCEL:
case SHOST_RECOVERY:
break;
default:
goto illegal;
}
break;
case SHOST_DEL_RECOVERY:
switch (oldstate) {
case SHOST_CANCEL_RECOVERY:
break;
default:
goto illegal;
}
break;
}
shost->shost_state = state;
return 0;
@@ -134,13 +154,24 @@ EXPORT_SYMBOL(scsi_host_set_state);
**/
void scsi_remove_host(struct Scsi_Host *shost)
{
unsigned long flags;
down(&shost->scan_mutex);
scsi_host_set_state(shost, SHOST_CANCEL);
spin_lock_irqsave(shost->host_lock, flags);
if (scsi_host_set_state(shost, SHOST_CANCEL))
if (scsi_host_set_state(shost, SHOST_CANCEL_RECOVERY)) {
spin_unlock_irqrestore(shost->host_lock, flags);
up(&shost->scan_mutex);
return;
}
spin_unlock_irqrestore(shost->host_lock, flags);
up(&shost->scan_mutex);
scsi_forget_host(shost);
scsi_proc_host_rm(shost);
scsi_host_set_state(shost, SHOST_DEL);
spin_lock_irqsave(shost->host_lock, flags);
if (scsi_host_set_state(shost, SHOST_DEL))
BUG_ON(scsi_host_set_state(shost, SHOST_DEL_RECOVERY));
spin_unlock_irqrestore(shost->host_lock, flags);
transport_unregister_device(&shost->shost_gendev);
class_device_unregister(&shost->shost_classdev);