Troubles with zvol + BIO_DELETE

[Matthew D. Fuller]

In some GELI messing, we've found some bad behavior in sending
DELETE's through to a backing zvol.  After investigation, my best
guess is that this is actually a bug in the zvol code.

The requests come into zvol_geom_start().  In "normal" cases (e.g.,
when doing a newfs directly on the zvol), the bio's seem to go
straight through to zvol_strategy().  However, when going through
GELI, we hit the !THREAD_CAN_SLEEP() case, and so they get queued up.

Then zvol_geom_worker() deals with them later.  However, it doesn't
know anything about BIO_DELETE; there's no handling at all.  So at
that point, the request just hangs around pending forever.  I'm pretty
sure it should just get send to zvol_strategy() the same as READ/WRITE
do:


Index: sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zvol.c
===================================================================
--- sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zvol.c	(revision 279210)
+++ sys/cddl/contrib/opensolaris/uts/common/fs/zfs/zvol.c	(working copy)
@@ -2775,6 +2775,7 @@
 			break;
 		case BIO_READ:
 		case BIO_WRITE:
+		case BIO_DELETE:
 			zvol_strategy(bp);
 			break;
 		}



-- 
Matthew Fuller     (MF4839)   |  fullermd at over-yonder.net
Systems/Network Administrator |  http://www.over-yonder.net/~fullermd/
           On the Internet, nobody can hear you scream.