diff mbox series

[2/5] scsi: introduce SHOST_BLOCKED state to support blocking IO

Message ID 20230325011734.507453-3-yebin@huaweicloud.com
State New
Headers
Series limit set the host state by sysfs |

Commit Message

Ye Bin March 25, 2023, 1:17 a.m. UTC 
  From: Ye Bin <yebin10@huawei.com>

SHOST_BLOCKED state to blocking io in block layer. This state use for
test, Only running state and blocked state can be switched to each
other.

Signed-off-by: Ye Bin <yebin10@huawei.com>
---
 drivers/scsi/hosts.c      | 11 +++++++++++
 drivers/scsi/scsi_sysfs.c |  1 +
 include/scsi/scsi_host.h  |  1 +
 3 files changed, 13 insertions(+)

Comments

Bart Van Assche March 27, 2023, 9:34 p.m. UTC | #1 
On 3/24/23 18:17, Ye Bin wrote:
> diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
> index 9b6fbbe15d92..3b497fd4d329 100644
> --- a/drivers/scsi/hosts.c
> +++ b/drivers/scsi/hosts.c
> @@ -90,6 +90,7 @@ int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state)
>   		switch (oldstate) {
>   		case SHOST_CREATED:
>   		case SHOST_RECOVERY:
> +		case SHOST_BLOCKED:
>   			break;
>   		default:
>   			goto illegal;
> @@ -99,6 +100,7 @@ int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state)
>   	case SHOST_RECOVERY:
>   		switch (oldstate) {
>   		case SHOST_RUNNING:
> +		case SHOST_BLOCKED:
>   			break;
>   		default:
>   			goto illegal;
> @@ -109,6 +111,7 @@ int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state)
>   		switch (oldstate) {
>   		case SHOST_CREATED:
>   		case SHOST_RUNNING:
> +		case SHOST_BLOCKED:
>   		case SHOST_CANCEL_RECOVERY:
>   			break;
>   		default:
> @@ -144,6 +147,14 @@ int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state)
>   			goto illegal;
>   		}
>   		break;
> +	case SHOST_BLOCKED:
> +		switch (oldstate) {
> +		case SHOST_RUNNING:
> +			break;
> +		default:
> +			goto illegal;
> +		}
> +		break;
>   	}

If a host is blocked, error recovery happens and completes, the host 
will be unblocked. I don't think that is acceptable.

The "blocked" property is orthogonal to the host state so a new boolean 
member variable should be introduced in struct Scsi_Host instead of 
introducing a new SCSI host state.

Thanks,

Bart.
diff mbox series

Patch

diff --git a/drivers/scsi/hosts.c b/drivers/scsi/hosts.c
index 9b6fbbe15d92..3b497fd4d329 100644
--- a/drivers/scsi/hosts.c
+++ b/drivers/scsi/hosts.c
@@ -90,6 +90,7 @@  int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state)
 		switch (oldstate) {
 		case SHOST_CREATED:
 		case SHOST_RECOVERY:
+		case SHOST_BLOCKED:
 			break;
 		default:
 			goto illegal;
@@ -99,6 +100,7 @@  int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state)
 	case SHOST_RECOVERY:
 		switch (oldstate) {
 		case SHOST_RUNNING:
+		case SHOST_BLOCKED:
 			break;
 		default:
 			goto illegal;
@@ -109,6 +111,7 @@  int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state)
 		switch (oldstate) {
 		case SHOST_CREATED:
 		case SHOST_RUNNING:
+		case SHOST_BLOCKED:
 		case SHOST_CANCEL_RECOVERY:
 			break;
 		default:
@@ -144,6 +147,14 @@  int scsi_host_set_state(struct Scsi_Host *shost, enum scsi_host_state state)
 			goto illegal;
 		}
 		break;
+	case SHOST_BLOCKED:
+		switch (oldstate) {
+		case SHOST_RUNNING:
+			break;
+		default:
+			goto illegal;
+		}
+		break;
 	}
 	shost->shost_state = state;
 	return 0;
diff --git a/drivers/scsi/scsi_sysfs.c b/drivers/scsi/scsi_sysfs.c
index cc0ae5e3def3..b14f95ac594e 100644
--- a/drivers/scsi/scsi_sysfs.c
+++ b/drivers/scsi/scsi_sysfs.c
@@ -69,6 +69,7 @@  static const struct {
 	{ SHOST_RECOVERY, "recovery" },
 	{ SHOST_CANCEL_RECOVERY, "cancel/recovery" },
 	{ SHOST_DEL_RECOVERY, "deleted/recovery", },
+	{ SHOST_BLOCKED, "blocked", },
 };
 const char *scsi_host_state_name(enum scsi_host_state state)
 {
diff --git a/include/scsi/scsi_host.h b/include/scsi/scsi_host.h
index 587cc767bb67..9e99317b11fa 100644
--- a/include/scsi/scsi_host.h
+++ b/include/scsi/scsi_host.h
@@ -527,6 +527,7 @@  enum scsi_host_state {
 	SHOST_RECOVERY,
 	SHOST_CANCEL_RECOVERY,
 	SHOST_DEL_RECOVERY,
+	SHOST_BLOCKED,
 };
 
 struct Scsi_Host {