Commit 22ed1307 authored Feb 17, 2010 by Christof Schmitt Committed by James Bottomley Feb 17, 2010

[SCSI] zfcp: Fix warnings from smatch

The smatch tool from http://repo.or.cz/w/smatch.git

warns about this:

drivers/s390/scsi/zfcp_scsi.c +64 zfcp_scsi_command_fail(5) warn: variable dereferenced before check 'scpnt->device'
drivers/s390/scsi/zfcp_scsi.c +64 zfcp_scsi_command_fail(5) warn: variable dereferenced before check 'scpnt->device->host'
drivers/s390/scsi/zfcp_scsi.c +93 zfcp_scsi_queuecommand(23) warn: variable dereferenced before check 'unit'

Fix the first two warnings by removing the checks for scpnt->device
and -> host: As long as the SCSI command exists, there is also a
scsi_device and a Scsi_Host.

Fix the last warning by removing the BUG_ON checks in
zfcp_scsi_queuecommand, they are leftovers from previous paranoia
about wrong pointers between data structures.

Reviewed-by: Swen Schillig <swen@vnet.ibm.com>
Signed-off-by: Christof Schmitt <christof.schmitt@de.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

parent 67feeeba

drivers/s390/scsi/zfcp_scsi.c

+2 −11

Original line number	Diff line number	Diff line
		@@ -60,10 +60,9 @@ static void zfcp_scsi_command_fail(struct scsi_cmnd *scpnt, int result)
		{
		struct zfcp_adapter *adapter =
		(struct zfcp_adapter *) scpnt->device->host->hostdata[0];

		set_host_byte(scpnt, result);
		if ((scpnt->device != NULL) && (scpnt->device->host != NULL))
		zfcp_dbf_scsi_result("fail", 4, adapter->dbf, scpnt, NULL);
		/* return directly */
		scpnt->scsi_done(scpnt);
		}

		@@ -87,14 +86,6 @@ static int zfcp_scsi_queuecommand(struct scsi_cmnd *scpnt,
		adapter = (struct zfcp_adapter *) scpnt->device->host->hostdata[0];
		unit = scpnt->device->hostdata;

		BUG_ON(!adapter \|\| (adapter != unit->port->adapter));
		BUG_ON(!scpnt->scsi_done);

		if (unlikely(!unit)) {
		zfcp_scsi_command_fail(scpnt, DID_NO_CONNECT);
		return 0;
		}

		scsi_result = fc_remote_port_chkready(rport);
		if (unlikely(scsi_result)) {
		scpnt->result = scsi_result;