mptfusion: tweak null pointer checks

Fixes the following smatch warnings:

  drivers/message/fusion/mptbase.c:652 mptbase_reply() warn: variable
    dereferenced before check 'reply' (see line 639)

      [JL: No-brainer, the enclosing switch statement dereferences
       reply, so we can't get here unless reply is valid.]

  drivers/message/fusion/mptsas.c:1255 mptsas_taskmgmt_complete() error:
    we previously assumed 'pScsiTmReply' could be null (see line 1227)

      [HCH: Reading the code in mptsas_taskmgmt_complete it's pretty
       obvious that it can't do anything useful if mr/pScsiTmReply are
       NULL, so I suspect it would be best to just return at the
       beginning of the function.

       I'd love to understand if it actually could ever be zero, which I
       doubt.  Maybe the LSI people can shed some light on that?]

  drivers/message/fusion/mptsas.c:3888 mptsas_not_responding_devices()
    error: we previously assumed 'port_info->phy_info' could be null
    (see line 3875)

      [HCH: It's pretty obvious from reading mptsas_sas_io_unit_pg0 that
       we never register a port_info with a NULL phy_info in the lists,
       so all NULL checks on it could be deleted.]

  drivers/message/fusion/mptscsih.c:1284 mptscsih_info() error:
    we previously assumed 'h' could be null (see line 1274)

      [HCH: shost_priv can't return NULL, so the if (h) should be
       removed.]

  drivers/message/fusion/mptscsih.c:1388 mptscsih_qcmd() error: we
    previously assumed 'vdevice' could be null (see line 1373)

      [HCH: vdevice can't ever be NULL here, it's allocated in
       ->slave_alloc and thus guaranteed to be around when
       ->queuecommand is called.]

Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com>
Acked-by: Sreekanth Reddy <Sreekanth.Reddy@avagotech.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

1 files changed, 4 insertions, 6 deletions

diff --git a/drivers/message/fusion/mptbase.c b/drivers/message/fusion/mptbase.c
index 9d4c7825a5f2..a896d948b79e 100644
--- a/drivers/message/fusion/mptbase.c
+++ b/drivers/message/fusion/mptbase.c
@@ -649,12 +649,10 @@ mptbase_reply(MPT_ADAPTER *ioc, MPT_FRAME_HDR *req, MPT_FRAME_HDR *reply)
 	case MPI_FUNCTION_CONFIG:
 	case MPI_FUNCTION_SAS_IO_UNIT_CONTROL:
 		ioc->mptbase_cmds.status |= MPT_MGMT_STATUS_COMMAND_GOOD;
-		if (reply) {
-			ioc->mptbase_cmds.status |= MPT_MGMT_STATUS_RF_VALID;
-			memcpy(ioc->mptbase_cmds.reply, reply,
-			    min(MPT_DEFAULT_FRAME_SIZE,
-				4 * reply->u.reply.MsgLength));
-		}
+		ioc->mptbase_cmds.status |= MPT_MGMT_STATUS_RF_VALID;
+		memcpy(ioc->mptbase_cmds.reply, reply,
+		    min(MPT_DEFAULT_FRAME_SIZE,
+			4 * reply->u.reply.MsgLength));
 		if (ioc->mptbase_cmds.status & MPT_MGMT_STATUS_PENDING) {
 			ioc->mptbase_cmds.status &= ~MPT_MGMT_STATUS_PENDING;
 			complete(&ioc->mptbase_cmds.done);