Re: [PATCH] tcm_qla2xxx Add SCSI command jammer/discard capability to the tcm_qla2xxx module

[Laurence Oberman <loberman@redhat.com>]

Hello Nicholas

Its fixed now.
Many Thanks.

$ scripts/checkpatch.pl 0001-tcm_qla2xxx-Add-SCSI-command-jammer-discard-capabili.patch
WARNING: added, moved or deleted file(s), does MAINTAINERS need updating?
#12: 
new file mode 100644

total: 0 errors, 1 warnings, 91 lines checked

0001-tcm_qla2xxx-Add-SCSI-command-jammer-discard-capabili.patch has style problems, please review.

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.



Tested by: Laurence Oberman <loberman@redhat.com>
Signed-off-by: Laurence Oberman <loberman@redhat.com>
---
 Documentation/scsi/tcm_qla2xxx.txt |   22 ++++++++++++++++++++++
 drivers/scsi/qla2xxx/Kconfig       |    9 +++++++++
 drivers/scsi/qla2xxx/tcm_qla2xxx.c |   20 ++++++++++++++++++++
 drivers/scsi/qla2xxx/tcm_qla2xxx.h |    1 +
 4 files changed, 52 insertions(+), 0 deletions(-)
 create mode 100644 Documentation/scsi/tcm_qla2xxx.txt

diff --git a/Documentation/scsi/tcm_qla2xxx.txt b/Documentation/scsi/tcm_qla2xxx.txt
new file mode 100644
index 0000000..c3a670a
--- /dev/null
+++ b/Documentation/scsi/tcm_qla2xxx.txt
@@ -0,0 +1,22 @@
+tcm_qla2xxx jam_host attribute
+------------------------------
+There is now a new module endpoint atribute called jam_host
+attribute: jam_host: boolean=0/1
+This attribute and accompanying code is only included if the
+Kconfig parameter TCM_QLA2XXX_DEBUG is set to Y
+By default this jammer code and functionality is disabled
+
+Use this attribute to control the discarding of SCSI commands to a
+selected host.
+This may be useful for testing error handling and simulating slow drain
+and other fabric issues.
+
+Setting a boolean of 1 for the jam_host attribute for a particular host
+ will discard the commands for that host.
+Reset back to 0 to stop the jamming.
+
+Enable host 4 to be jammed
+echo 1 > /sys/kernel/config/target/qla2xxx/21:00:00:24:ff:27:8f:ae/tpgt_1/attrib/jam_host
+
+Disable jamming on host 4
+echo 0 > /sys/kernel/config/target/qla2xxx/21:00:00:24:ff:27:8f:ae/tpgt_1/attrib/jam_host
diff --git a/drivers/scsi/qla2xxx/Kconfig b/drivers/scsi/qla2xxx/Kconfig
index 10aa18b..67c0d5a 100644
--- a/drivers/scsi/qla2xxx/Kconfig
+++ b/drivers/scsi/qla2xxx/Kconfig
@@ -36,3 +36,12 @@ config TCM_QLA2XXX
 	default n
 	---help---
 	Say Y here to enable the TCM_QLA2XXX fabric module for QLogic 24xx+ series target mode HBAs
+
+if TCM_QLA2XXX
+config TCM_QLA2XXX_DEBUG
+	bool "TCM_QLA2XXX fabric module DEBUG mode for QLogic 24xx+ series target mode HBAs"
+	default n
+	---help---
+	Say Y here to enable the TCM_QLA2XXX fabric module DEBUG for QLogic 24xx+ series target mode HBAs
+	This will include code to enable the SCSI command jammer
+endif
diff --git a/drivers/scsi/qla2xxx/tcm_qla2xxx.c b/drivers/scsi/qla2xxx/tcm_qla2xxx.c
index 1808a01..948224e 100644
--- a/drivers/scsi/qla2xxx/tcm_qla2xxx.c
+++ b/drivers/scsi/qla2xxx/tcm_qla2xxx.c
@@ -457,6 +457,10 @@ static int tcm_qla2xxx_handle_cmd(scsi_qla_host_t *vha, struct qla_tgt_cmd *cmd,
 	struct se_cmd *se_cmd = &cmd->se_cmd;
 	struct se_session *se_sess;
 	struct qla_tgt_sess *sess;
+#ifdef CONFIG_TCM_QLA2XXX_DEBUG
+	struct se_portal_group *se_tpg;
+	struct tcm_qla2xxx_tpg *tpg;
+#endif
 	int flags = TARGET_SCF_ACK_KREF;
 
 	if (bidi)
@@ -477,6 +481,15 @@ static int tcm_qla2xxx_handle_cmd(scsi_qla_host_t *vha, struct qla_tgt_cmd *cmd,
 		return -EINVAL;
 	}
 
+#ifdef CONFIG_TCM_QLA2XXX_DEBUG
+	se_tpg = se_sess->se_tpg;
+	tpg = container_of(se_tpg, struct tcm_qla2xxx_tpg, se_tpg);
+	if (unlikely(tpg->tpg_attrib.jam_host)) {
+		/* return, and dont run target_submit_cmd,discarding command */
+		return 0;
+	}
+#endif
+
 	cmd->vha->tgt_counters.qla_core_sbt_cmd++;
 	return target_submit_cmd(se_cmd, se_sess, cdb, &cmd->sense_buffer[0],
 				cmd->unpacked_lun, data_length, fcp_task_attr,
@@ -844,6 +857,9 @@ DEF_QLA_TPG_ATTRIB(cache_dynamic_acls);
 DEF_QLA_TPG_ATTRIB(demo_mode_write_protect);
 DEF_QLA_TPG_ATTRIB(prod_mode_write_protect);
 DEF_QLA_TPG_ATTRIB(demo_mode_login_only);
+#ifdef CONFIG_TCM_QLA2XXX_DEBUG
+DEF_QLA_TPG_ATTRIB(jam_host);
+#endif
 
 static struct configfs_attribute *tcm_qla2xxx_tpg_attrib_attrs[] = {
 	&tcm_qla2xxx_tpg_attrib_attr_generate_node_acls,
@@ -851,6 +867,9 @@ static struct configfs_attribute *tcm_qla2xxx_tpg_attrib_attrs[] = {
 	&tcm_qla2xxx_tpg_attrib_attr_demo_mode_write_protect,
 	&tcm_qla2xxx_tpg_attrib_attr_prod_mode_write_protect,
 	&tcm_qla2xxx_tpg_attrib_attr_demo_mode_login_only,
+#ifdef CONFIG_TCM_QLA2XXX_DEBUG
+	&tcm_qla2xxx_tpg_attrib_attr_jam_host,
+#endif
 	NULL,
 };
 
@@ -1023,6 +1042,7 @@ static struct se_portal_group *tcm_qla2xxx_make_tpg(
 	tpg->tpg_attrib.demo_mode_write_protect = 1;
 	tpg->tpg_attrib.cache_dynamic_acls = 1;
 	tpg->tpg_attrib.demo_mode_login_only = 1;
+	tpg->tpg_attrib.jam_host = 0;
 
 	ret = core_tpg_register(wwn, &tpg->se_tpg, SCSI_PROTOCOL_FCP);
 	if (ret < 0) {
diff --git a/drivers/scsi/qla2xxx/tcm_qla2xxx.h b/drivers/scsi/qla2xxx/tcm_qla2xxx.h
index 3bbf4cb..37e026a 100644
--- a/drivers/scsi/qla2xxx/tcm_qla2xxx.h
+++ b/drivers/scsi/qla2xxx/tcm_qla2xxx.h
@@ -34,6 +34,7 @@ struct tcm_qla2xxx_tpg_attrib {
 	int prod_mode_write_protect;
 	int demo_mode_login_only;
 	int fabric_prot_type;
+	int jam_host;
 };
 
 struct tcm_qla2xxx_tpg {
-- 
1.7.1


Laurence Oberman
Principal Software Maintenance Engineer
Red Hat Global Support Services

----- Original Message -----
From: "Nicholas A. Bellinger" <nab@linux-iscsi.org>
To: "Laurence Oberman" <loberman@redhat.com>
Cc: "Himanshu Madhani" <himanshu.madhani@qlogic.com>, "Bart Van Assche" <bart.vanassche@sandisk.com>, "linux-scsi" <linux-scsi@vger.kernel.org>, "target-devel" <target-devel@vger.kernel.org>, "Quinn Tran" <quinn.tran@qlogic.com>
Sent: Monday, April 4, 2016 4:54:11 PM
Subject: Re: [PATCH]  tcm_qla2xxx Add SCSI command jammer/discard capability to the tcm_qla2xxx module

On Sun, 2016-04-03 at 09:57 -0400, Laurence Oberman wrote:
> Hi Nicholas
> 
> Apologies for the top posting, that was in my haste to correct the prior patch that had the typo.
> When I investigated the attributes it looked like I would have had to create a store and a check function and call the check function each time.
> That was my lack of understanding of the functionality.
> 
> I also looked at your example and in my case I needed a way to set the attribute to a number matching the host#.
> When I tested this I was only able to set boolean values of 1 or 0 for the attributes and the definition of
> tcm_qla2xxx_tpg_attrib_##name##_store validates that only booleans of 1 or 0 are supported.
> 
> However after your email I then realized using a boolean on the endpoints below will work here.
> Thank you for taking the time to show me, it was very helpful.
> 
> sys]# find . -name jam_host
> ./kernel/config/target/qla2xxx/21:00:00:24:ff:27:8f:ae/tpgt_1/attrib/jam_host
> ./kernel/config/target/qla2xxx/21:00:00:24:ff:27:8f:af/tpgt_1/attrib/jam_host
> 
> I tested this and here are the patches in the format you require.
> Hopefully this new functionality will be useful for others.
> I am not set for emailing directly from git.
> 
> Tested by: Laurence Oberman <loberman@redhat.com>
> Signed-off-by: Laurence Oberman <loberman@redhat.com>
> ---
>  drivers/scsi/qla2xxx/Kconfig       |   11 +++++++++++
>  drivers/scsi/qla2xxx/tcm_qla2xxx.c |   20 ++++++++++++++++++++
>  drivers/scsi/qla2xxx/tcm_qla2xxx.h |    1 +
>  3 files changed, 32 insertions(+), 0 deletions(-)
> 
> diff --git a/drivers/scsi/qla2xxx/Kconfig b/drivers/scsi/qla2xxx/Kconfig
> index 10aa18b..5110fab 100644
> --- a/drivers/scsi/qla2xxx/Kconfig
> +++ b/drivers/scsi/qla2xxx/Kconfig
> @@ -36,3 +36,14 @@ config TCM_QLA2XXX
>  	default n
>  	---help---
>  	Say Y here to enable the TCM_QLA2XXX fabric module for QLogic 24xx+ series target mode HBAs
> +
> +config TCM_QLA2XXX_DEBUG
> +	bool "TCM_QLA2XXX fabric module DEBUG mode for QLogic 24xx+ series target mode HBAs"
> +	depends on SCSI_QLA_FC && TARGET_CORE
> +	depends on LIBFC
> +	select BTREE
> +	default n
> +	---help---
> +	Say Y here to enable the TCM_QLA2XXX fabric module DEBUG for QLogic 24xx+ series target mode HBAs
> +	This will include code to enable the SCSI command jammer
> +

Instead of duplicating the 'depends' here for TCM_QLA2XXX, just do a:

if TCM_QLA2XXX

config TCM_QLA2XXX_DEBUG
...
...

endif

> diff --git a/drivers/scsi/qla2xxx/tcm_qla2xxx.c b/drivers/scsi/qla2xxx/tcm_qla2xxx.c
> index 1808a01..411a450 100644
> --- a/drivers/scsi/qla2xxx/tcm_qla2xxx.c
> +++ b/drivers/scsi/qla2xxx/tcm_qla2xxx.c
> @@ -457,6 +457,10 @@ static int tcm_qla2xxx_handle_cmd(scsi_qla_host_t *vha, struct qla_tgt_cmd *cmd,
>  	struct se_cmd *se_cmd = &cmd->se_cmd;
>  	struct se_session *se_sess;
>  	struct qla_tgt_sess *sess;
> +#ifdef CONFIG_TCM_QLA2XXX_DEBUG
> +        struct se_portal_group *se_tpg;
> +        struct tcm_qla2xxx_tpg *tpg;
> +#endif

Whitespace instead of TAB here.

>  	int flags = TARGET_SCF_ACK_KREF;
>  
>  	if (bidi)
> @@ -476,6 +480,15 @@ static int tcm_qla2xxx_handle_cmd(scsi_qla_host_t *vha, struct qla_tgt_cmd *cmd,
>  		pr_err("Unable to locate active struct se_session\n");
>  		return -EINVAL;
>  	}
> + 
> +#ifdef CONFIG_TCM_QLA2XXX_DEBUG
> +	se_tpg = se_sess->se_tpg;
> +	tpg = container_of(se_tpg,struct tcm_qla2xxx_tpg, se_tpg);
> + 	if (unlikely(tpg->tpg_attrib.jam_host)) {
> + 		/* return, and dont run target_submit_cmd,discarding command */
> +                return 0;
> +	}
> +#endif

Whitespace instead of TABs here too.

>  
>  	cmd->vha->tgt_counters.qla_core_sbt_cmd++;
>  	return target_submit_cmd(se_cmd, se_sess, cdb, &cmd->sense_buffer[0],
> @@ -844,6 +857,9 @@ DEF_QLA_TPG_ATTRIB(cache_dynamic_acls);
>  DEF_QLA_TPG_ATTRIB(demo_mode_write_protect);
>  DEF_QLA_TPG_ATTRIB(prod_mode_write_protect);
>  DEF_QLA_TPG_ATTRIB(demo_mode_login_only);
> +#ifdef CONFIG_TCM_QLA2XXX_DEBUG
> +DEF_QLA_TPG_ATTRIB(jam_host);
> +#endif
>  
>  static struct configfs_attribute *tcm_qla2xxx_tpg_attrib_attrs[] = {
>  	&tcm_qla2xxx_tpg_attrib_attr_generate_node_acls,
> @@ -851,6 +867,9 @@ static struct configfs_attribute *tcm_qla2xxx_tpg_attrib_attrs[] = {
>  	&tcm_qla2xxx_tpg_attrib_attr_demo_mode_write_protect,
>  	&tcm_qla2xxx_tpg_attrib_attr_prod_mode_write_protect,
>  	&tcm_qla2xxx_tpg_attrib_attr_demo_mode_login_only,
> +#ifdef CONFIG_TCM_QLA2XXX_DEBUG
> +        &tcm_qla2xxx_tpg_attrib_attr_jam_host,
> +#endif
>  	NULL,
>  };

Whitespace instead of TABs here too.