From mboxrd@z Thu Jan 1 00:00:00 1970 From: walter harms Date: Tue, 02 Oct 2012 11:48:57 +0000 Subject: Re: [patch] target/iscsi: precedence bug in iscsit_set_dataout_sequence_values() Message-Id: <506AD4A9.2050702@bfs.de> List-Id: References: <20121002082248.GB12398@elgon.mountain> In-Reply-To: <20121002082248.GB12398@elgon.mountain> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Dan Carpenter Cc: "Nicholas A. Bellinger" , Andy Grover , Christoph Hellwig , linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, kernel-janitors@vger.kernel.org Am 02.10.2012 10:22, schrieb Dan Carpenter: > Clang warns about this bug: > drivers/target/iscsi/iscsi_target_erl0.c:52:45: warning: operator '?:' > has lower precedence than '+'; '+' will be evaluated first > [-Wparentheses] > > Signed-off-by: Dan Carpenter > --- > Please review this very carefully because I haven't tested it. It could > be that the check should be: > (data_done + data_length > FirstBurstLength) ? FirstBurstLength : data_length); > Instead of what I have which is: > data_done + (data_length > FirstBurstLength ? FirstBurstLength : data_length); > > diff --git a/drivers/target/iscsi/iscsi_target_erl0.c b/drivers/target/iscsi/iscsi_target_erl0.c > index 1a02016..2067efd 100644 > --- a/drivers/target/iscsi/iscsi_target_erl0.c > +++ b/drivers/target/iscsi/iscsi_target_erl0.c > @@ -48,9 +48,9 @@ void iscsit_set_dataout_sequence_values( > if (cmd->unsolicited_data) { > cmd->seq_start_offset = cmd->write_data_done; > cmd->seq_end_offset = (cmd->write_data_done + > - (cmd->se_cmd.data_length > > - conn->sess->sess_ops->FirstBurstLength) ? > - conn->sess->sess_ops->FirstBurstLength : cmd->se_cmd.data_length); > + ((cmd->se_cmd.data_length > > + conn->sess->sess_ops->FirstBurstLength) ? > + conn->sess->sess_ops->FirstBurstLength : cmd->se_cmd.data_length)); > return; > } > the ?: operator is nice but at a certain length is starts to become unreadable, the end is normally calculated by end= start+len; Therefor i suggest: if ( cmd->se_cmd.data_length > conn->sess->sess_ops->FirstBurstLength ) cmd->seq_end_offset = cmd->seq_start_offset + conn->sess->sess_ops->FirstBurstLength; else cmd->seq_end_offset = cmd->seq_start_offset + cmd->se_cmd.data_length; just my 2 cents, re, wh