* [PATCH] virtio-scsi: hotplug suppot for virtio-scsi
@ 2012-06-20 6:55 Cong Meng
2012-07-01 13:24 ` Paolo Bonzini
0 siblings, 1 reply; 4+ messages in thread
From: Cong Meng @ 2012-06-20 6:55 UTC (permalink / raw)
To: Paolo Bonzini
Cc: Rusty Russell, Nicholas A. Bellinger, stefanha, linuxram,
Anthony Liguori, senwang, zwanp, James E.J. Bottomley,
virtualization, linux-kernel, linux-scsi, Cong Meng
This patch implements the hotplug support for virtio-scsi.
When there is a device attached/detached, the virtio-scsi driver will be
signaled via event virtual queue and it will add/remove the scsi device
in question automatically.
Signed-off-by: Cong Meng <mc@linux.vnet.ibm.com>
Signed-off-by: Sen Wang <senwang@linux.vnet.ibm.com>
---
drivers/scsi/virtio_scsi.c | 109 ++++++++++++++++++++++++++++++++++++++++++-
include/linux/virtio_scsi.h | 9 ++++
2 files changed, 116 insertions(+), 2 deletions(-)
diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index 1b38431..6dad625 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -25,6 +25,7 @@
#include <scsi/scsi_cmnd.h>
#define VIRTIO_SCSI_MEMPOOL_SZ 64
+#define VIRTIO_SCSI_EVENT_LEN 8
/* Command queue element */
struct virtio_scsi_cmd {
@@ -43,9 +44,15 @@ struct virtio_scsi_cmd {
} resp;
} ____cacheline_aligned_in_smp;
+struct virtio_scsi_event_node {
+ struct virtio_scsi *vscsi;
+ struct virtio_scsi_event event;
+ struct work_struct work;
+};
+
/* Driver instance state */
struct virtio_scsi {
- /* Protects ctrl_vq, req_vq and sg[] */
+ /* Protects ctrl_vq, event_vq, req_vq and sg[] */
spinlock_t vq_lock;
struct virtio_device *vdev;
@@ -53,6 +60,9 @@ struct virtio_scsi {
struct virtqueue *event_vq;
struct virtqueue *req_vq;
+ /* Get some buffers reday for event vq */
+ struct virtio_scsi_event_node event_list[VIRTIO_SCSI_EVENT_LEN];
+
/* For sglist construction when adding commands to the virtqueue. */
struct scatterlist sg[];
};
@@ -184,9 +194,93 @@ static void virtscsi_ctrl_done(struct virtqueue *vq)
virtscsi_vq_done(vq, virtscsi_complete_free);
};
+static int virtscsi_kick_event(struct virtio_scsi *vscsi,
+ struct virtio_scsi_event_node *event_node)
+{
+ int ret;
+ struct scatterlist sg;
+ unsigned long flags;
+
+ sg_set_buf(&sg, &event_node->event, sizeof(struct virtio_scsi_event));
+
+ spin_lock_irqsave(&vscsi->vq_lock, flags);
+
+ ret = virtqueue_add_buf(vscsi->event_vq, &sg, 0, 1, event_node, GFP_ATOMIC);
+ if (ret >= 0)
+ virtqueue_kick(vscsi->event_vq);
+
+ spin_unlock_irqrestore(&vscsi->vq_lock, flags);
+
+ return ret;
+}
+
+static int virtscsi_kick_event_all(struct virtio_scsi *vscsi)
+{
+ int i;
+
+ for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++) {
+ vscsi->event_list[i].vscsi = vscsi;
+ virtscsi_kick_event(vscsi, &vscsi->event_list[i]);
+ }
+
+ return 0;
+}
+
+static void virtscsi_handle_transport_reset(struct virtio_scsi *vscsi,
+ struct virtio_scsi_event *event)
+{
+ struct scsi_device *sdev;
+ struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
+ unsigned int target = event->lun[1];
+ unsigned int lun = (event->lun[2] << 8) | event->lun[3];
+
+ switch (event->reason) {
+ case VIRTIO_SCSI_EVT_RESET_RESCAN:
+ scsi_add_device(shost, 0, target, lun);
+ break;
+ case VIRTIO_SCSI_EVT_RESET_REMOVED:
+ sdev = scsi_device_lookup(shost, 0, target, lun);
+ if (sdev) {
+ scsi_remove_device(sdev);
+ scsi_device_put(sdev);
+ } else {
+ pr_err("SCSI device %d 0 %d %d not found\n",
+ shost->host_no, target, lun);
+ }
+ break;
+ default:
+ pr_info("Unsupport virtio scsi event reason %x\n", event->reason);
+ }
+}
+
+static void virtscsi_handle_event(struct work_struct *work)
+{
+ struct virtio_scsi_event_node *event_node =
+ container_of(work, struct virtio_scsi_event_node, work);
+ struct virtio_scsi *vscsi = event_node->vscsi;
+ struct virtio_scsi_event *event = &event_node->event;
+
+ switch (event->event) {
+ case VIRTIO_SCSI_T_TRANSPORT_RESET:
+ virtscsi_handle_transport_reset(vscsi, event);
+ break;
+ default:
+ pr_err("Unsupport virtio scsi event %x\n", event->event);
+ }
+ virtscsi_kick_event(vscsi, event_node);
+}
+
+static void virtscsi_complete_event(void *buf)
+{
+ struct virtio_scsi_event_node *event_node = buf;
+
+ INIT_WORK(&event_node->work, virtscsi_handle_event);
+ schedule_work(&event_node->work);
+}
+
static void virtscsi_event_done(struct virtqueue *vq)
{
- virtscsi_vq_done(vq, virtscsi_complete_free);
+ virtscsi_vq_done(vq, virtscsi_complete_event);
};
static void virtscsi_map_sgl(struct scatterlist *sg, unsigned int *p_idx,
@@ -435,6 +529,11 @@ static int virtscsi_init(struct virtio_device *vdev,
virtscsi_config_set(vdev, cdb_size, VIRTIO_SCSI_CDB_SIZE);
virtscsi_config_set(vdev, sense_size, VIRTIO_SCSI_SENSE_SIZE);
+
+ if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) {
+ virtscsi_kick_event_all(vscsi);
+ }
+
return 0;
}
@@ -532,7 +631,13 @@ static struct virtio_device_id id_table[] = {
{ 0 },
};
+static unsigned int features[] = {
+ VIRTIO_SCSI_F_HOTPLUG
+};
+
static struct virtio_driver virtio_scsi_driver = {
+ .feature_table = features,
+ .feature_table_size = ARRAY_SIZE(features),
.driver.name = KBUILD_MODNAME,
.driver.owner = THIS_MODULE,
.id_table = id_table,
diff --git a/include/linux/virtio_scsi.h b/include/linux/virtio_scsi.h
index 8ddeafd..dc8d305 100644
--- a/include/linux/virtio_scsi.h
+++ b/include/linux/virtio_scsi.h
@@ -69,6 +69,10 @@ struct virtio_scsi_config {
u32 max_lun;
} __packed;
+/* Feature Bits */
+#define VIRTIO_SCSI_F_INOUT 0
+#define VIRTIO_SCSI_F_HOTPLUG 1
+
/* Response codes */
#define VIRTIO_SCSI_S_OK 0
#define VIRTIO_SCSI_S_OVERRUN 1
@@ -105,6 +109,11 @@ struct virtio_scsi_config {
#define VIRTIO_SCSI_T_TRANSPORT_RESET 1
#define VIRTIO_SCSI_T_ASYNC_NOTIFY 2
+/* Reasons of transport reset event */
+#define VIRTIO_SCSI_EVT_RESET_HARD 0
+#define VIRTIO_SCSI_EVT_RESET_RESCAN 1
+#define VIRTIO_SCSI_EVT_RESET_REMOVED 2
+
#define VIRTIO_SCSI_S_SIMPLE 0
#define VIRTIO_SCSI_S_ORDERED 1
#define VIRTIO_SCSI_S_HEAD 2
--
1.7.7.6
^ permalink raw reply related [flat|nested] 4+ messages in thread
* Re: [PATCH] virtio-scsi: hotplug suppot for virtio-scsi
2012-06-20 6:55 [PATCH] virtio-scsi: hotplug suppot for virtio-scsi Cong Meng
@ 2012-07-01 13:24 ` Paolo Bonzini
2012-07-02 7:20 ` mc
0 siblings, 1 reply; 4+ messages in thread
From: Paolo Bonzini @ 2012-07-01 13:24 UTC (permalink / raw)
To: Cong Meng
Cc: Rusty Russell, Nicholas A. Bellinger, stefanha, linuxram,
Anthony Liguori, senwang, zwanp, James E.J. Bottomley,
virtualization, linux-kernel, linux-scsi
Il 20/06/2012 08:55, Cong Meng ha scritto:
> This patch implements the hotplug support for virtio-scsi.
> When there is a device attached/detached, the virtio-scsi driver will be
> signaled via event virtual queue and it will add/remove the scsi device
> in question automatically.
>
> Signed-off-by: Cong Meng <mc@linux.vnet.ibm.com>
> Signed-off-by: Sen Wang <senwang@linux.vnet.ibm.com>
Looks good (with one nit below), but please rebase over the four patches
at http://permalink.gmane.org/gmane.linux.kernel/1312496
> ---
> drivers/scsi/virtio_scsi.c | 109 ++++++++++++++++++++++++++++++++++++++++++-
> include/linux/virtio_scsi.h | 9 ++++
> 2 files changed, 116 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
> index 1b38431..6dad625 100644
> --- a/drivers/scsi/virtio_scsi.c
> +++ b/drivers/scsi/virtio_scsi.c
> @@ -25,6 +25,7 @@
> #include <scsi/scsi_cmnd.h>
>
> #define VIRTIO_SCSI_MEMPOOL_SZ 64
> +#define VIRTIO_SCSI_EVENT_LEN 8
>
> /* Command queue element */
> struct virtio_scsi_cmd {
> @@ -43,9 +44,15 @@ struct virtio_scsi_cmd {
> } resp;
> } ____cacheline_aligned_in_smp;
>
> +struct virtio_scsi_event_node {
> + struct virtio_scsi *vscsi;
> + struct virtio_scsi_event event;
> + struct work_struct work;
> +};
> +
> /* Driver instance state */
> struct virtio_scsi {
> - /* Protects ctrl_vq, req_vq and sg[] */
> + /* Protects ctrl_vq, event_vq, req_vq and sg[] */
> spinlock_t vq_lock;
>
> struct virtio_device *vdev;
> @@ -53,6 +60,9 @@ struct virtio_scsi {
> struct virtqueue *event_vq;
> struct virtqueue *req_vq;
>
> + /* Get some buffers reday for event vq */
> + struct virtio_scsi_event_node event_list[VIRTIO_SCSI_EVENT_LEN];
> +
> /* For sglist construction when adding commands to the virtqueue. */
> struct scatterlist sg[];
> };
> @@ -184,9 +194,93 @@ static void virtscsi_ctrl_done(struct virtqueue *vq)
> virtscsi_vq_done(vq, virtscsi_complete_free);
> };
>
> +static int virtscsi_kick_event(struct virtio_scsi *vscsi,
> + struct virtio_scsi_event_node *event_node)
> +{
> + int ret;
> + struct scatterlist sg;
> + unsigned long flags;
> +
> + sg_set_buf(&sg, &event_node->event, sizeof(struct virtio_scsi_event));
> +
> + spin_lock_irqsave(&vscsi->vq_lock, flags);
> +
> + ret = virtqueue_add_buf(vscsi->event_vq, &sg, 0, 1, event_node, GFP_ATOMIC);
> + if (ret >= 0)
> + virtqueue_kick(vscsi->event_vq);
> +
> + spin_unlock_irqrestore(&vscsi->vq_lock, flags);
> +
> + return ret;
> +}
> +
> +static int virtscsi_kick_event_all(struct virtio_scsi *vscsi)
> +{
> + int i;
> +
> + for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++) {
> + vscsi->event_list[i].vscsi = vscsi;
> + virtscsi_kick_event(vscsi, &vscsi->event_list[i]);
> + }
> +
> + return 0;
> +}
> +
> +static void virtscsi_handle_transport_reset(struct virtio_scsi *vscsi,
> + struct virtio_scsi_event *event)
> +{
> + struct scsi_device *sdev;
> + struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
> + unsigned int target = event->lun[1];
> + unsigned int lun = (event->lun[2] << 8) | event->lun[3];
> +
> + switch (event->reason) {
> + case VIRTIO_SCSI_EVT_RESET_RESCAN:
> + scsi_add_device(shost, 0, target, lun);
> + break;
> + case VIRTIO_SCSI_EVT_RESET_REMOVED:
> + sdev = scsi_device_lookup(shost, 0, target, lun);
> + if (sdev) {
> + scsi_remove_device(sdev);
> + scsi_device_put(sdev);
> + } else {
> + pr_err("SCSI device %d 0 %d %d not found\n",
> + shost->host_no, target, lun);
> + }
> + break;
> + default:
> + pr_info("Unsupport virtio scsi event reason %x\n", event->reason);
> + }
> +}
> +
> +static void virtscsi_handle_event(struct work_struct *work)
> +{
> + struct virtio_scsi_event_node *event_node =
> + container_of(work, struct virtio_scsi_event_node, work);
> + struct virtio_scsi *vscsi = event_node->vscsi;
> + struct virtio_scsi_event *event = &event_node->event;
> +
> + switch (event->event) {
> + case VIRTIO_SCSI_T_TRANSPORT_RESET:
> + virtscsi_handle_transport_reset(vscsi, event);
> + break;
Please handle VIRTIO_SCSI_T_NO_EVENT too here, and mask out
VIRTIO_SCSI_T_EVENTS_MISSED even if you do not handle it by triggering a
full rescan.
Paolo
> + default:
> + pr_err("Unsupport virtio scsi event %x\n", event->event);
> + }
> + virtscsi_kick_event(vscsi, event_node);
> +}
> +
> +static void virtscsi_complete_event(void *buf)
> +{
> + struct virtio_scsi_event_node *event_node = buf;
> +
> + INIT_WORK(&event_node->work, virtscsi_handle_event);
> + schedule_work(&event_node->work);
> +}
> +
> static void virtscsi_event_done(struct virtqueue *vq)
> {
> - virtscsi_vq_done(vq, virtscsi_complete_free);
> + virtscsi_vq_done(vq, virtscsi_complete_event);
> };
>
> static void virtscsi_map_sgl(struct scatterlist *sg, unsigned int *p_idx,
> @@ -435,6 +529,11 @@ static int virtscsi_init(struct virtio_device *vdev,
>
> virtscsi_config_set(vdev, cdb_size, VIRTIO_SCSI_CDB_SIZE);
> virtscsi_config_set(vdev, sense_size, VIRTIO_SCSI_SENSE_SIZE);
> +
> + if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) {
> + virtscsi_kick_event_all(vscsi);
> + }
> +
> return 0;
> }
>
> @@ -532,7 +631,13 @@ static struct virtio_device_id id_table[] = {
> { 0 },
> };
>
> +static unsigned int features[] = {
> + VIRTIO_SCSI_F_HOTPLUG
> +};
> +
> static struct virtio_driver virtio_scsi_driver = {
> + .feature_table = features,
> + .feature_table_size = ARRAY_SIZE(features),
> .driver.name = KBUILD_MODNAME,
> .driver.owner = THIS_MODULE,
> .id_table = id_table,
> diff --git a/include/linux/virtio_scsi.h b/include/linux/virtio_scsi.h
> index 8ddeafd..dc8d305 100644
> --- a/include/linux/virtio_scsi.h
> +++ b/include/linux/virtio_scsi.h
> @@ -69,6 +69,10 @@ struct virtio_scsi_config {
> u32 max_lun;
> } __packed;
>
> +/* Feature Bits */
> +#define VIRTIO_SCSI_F_INOUT 0
> +#define VIRTIO_SCSI_F_HOTPLUG 1
> +
> /* Response codes */
> #define VIRTIO_SCSI_S_OK 0
> #define VIRTIO_SCSI_S_OVERRUN 1
> @@ -105,6 +109,11 @@ struct virtio_scsi_config {
> #define VIRTIO_SCSI_T_TRANSPORT_RESET 1
> #define VIRTIO_SCSI_T_ASYNC_NOTIFY 2
>
> +/* Reasons of transport reset event */
> +#define VIRTIO_SCSI_EVT_RESET_HARD 0
> +#define VIRTIO_SCSI_EVT_RESET_RESCAN 1
> +#define VIRTIO_SCSI_EVT_RESET_REMOVED 2
> +
> #define VIRTIO_SCSI_S_SIMPLE 0
> #define VIRTIO_SCSI_S_ORDERED 1
> #define VIRTIO_SCSI_S_HEAD 2
>
Thanks,
Paolo
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] virtio-scsi: hotplug suppot for virtio-scsi
2012-07-01 13:24 ` Paolo Bonzini
@ 2012-07-02 7:20 ` mc
2012-07-02 8:11 ` Paolo Bonzini
0 siblings, 1 reply; 4+ messages in thread
From: mc @ 2012-07-02 7:20 UTC (permalink / raw)
To: Paolo Bonzini
Cc: Rusty Russell, Nicholas A. Bellinger, stefanha, linuxram,
Anthony Liguori, senwang, zwanp, James E.J. Bottomley,
virtualization, linux-kernel, linux-scsi
Quoting Paolo Bonzini <pbonzini@redhat.com>:
> Il 20/06/2012 08:55, Cong Meng ha scritto:
>> This patch implements the hotplug support for virtio-scsi.
>> When there is a device attached/detached, the virtio-scsi driver will be
>> signaled via event virtual queue and it will add/remove the scsi device
>> in question automatically.
>>
>> Signed-off-by: Cong Meng <mc@linux.vnet.ibm.com>
>> Signed-off-by: Sen Wang <senwang@linux.vnet.ibm.com>
>
> Looks good (with one nit below), but please rebase over the four patches
> at http://permalink.gmane.org/gmane.linux.kernel/1312496
>
>> ---
>> drivers/scsi/virtio_scsi.c | 109
>> ++++++++++++++++++++++++++++++++++++++++++-
>> include/linux/virtio_scsi.h | 9 ++++
>> 2 files changed, 116 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
>> index 1b38431..6dad625 100644
>> --- a/drivers/scsi/virtio_scsi.c
>> +++ b/drivers/scsi/virtio_scsi.c
>> @@ -25,6 +25,7 @@
>> #include <scsi/scsi_cmnd.h>
>>
>> #define VIRTIO_SCSI_MEMPOOL_SZ 64
>> +#define VIRTIO_SCSI_EVENT_LEN 8
>>
>> /* Command queue element */
>> struct virtio_scsi_cmd {
>> @@ -43,9 +44,15 @@ struct virtio_scsi_cmd {
>> } resp;
>> } ____cacheline_aligned_in_smp;
>>
>> +struct virtio_scsi_event_node {
>> + struct virtio_scsi *vscsi;
>> + struct virtio_scsi_event event;
>> + struct work_struct work;
>> +};
>> +
>> /* Driver instance state */
>> struct virtio_scsi {
>> - /* Protects ctrl_vq, req_vq and sg[] */
>> + /* Protects ctrl_vq, event_vq, req_vq and sg[] */
>> spinlock_t vq_lock;
>>
>> struct virtio_device *vdev;
>> @@ -53,6 +60,9 @@ struct virtio_scsi {
>> struct virtqueue *event_vq;
>> struct virtqueue *req_vq;
>>
>> + /* Get some buffers reday for event vq */
>> + struct virtio_scsi_event_node event_list[VIRTIO_SCSI_EVENT_LEN];
>> +
>> /* For sglist construction when adding commands to the virtqueue. */
>> struct scatterlist sg[];
>> };
>> @@ -184,9 +194,93 @@ static void virtscsi_ctrl_done(struct virtqueue *vq)
>> virtscsi_vq_done(vq, virtscsi_complete_free);
>> };
>>
>> +static int virtscsi_kick_event(struct virtio_scsi *vscsi,
>> + struct virtio_scsi_event_node *event_node)
>> +{
>> + int ret;
>> + struct scatterlist sg;
>> + unsigned long flags;
>> +
>> + sg_set_buf(&sg, &event_node->event, sizeof(struct virtio_scsi_event));
>> +
>> + spin_lock_irqsave(&vscsi->vq_lock, flags);
>> +
>> + ret = virtqueue_add_buf(vscsi->event_vq, &sg, 0, 1, event_node,
>> GFP_ATOMIC);
>> + if (ret >= 0)
>> + virtqueue_kick(vscsi->event_vq);
>> +
>> + spin_unlock_irqrestore(&vscsi->vq_lock, flags);
>> +
>> + return ret;
>> +}
>> +
>> +static int virtscsi_kick_event_all(struct virtio_scsi *vscsi)
>> +{
>> + int i;
>> +
>> + for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++) {
>> + vscsi->event_list[i].vscsi = vscsi;
>> + virtscsi_kick_event(vscsi, &vscsi->event_list[i]);
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static void virtscsi_handle_transport_reset(struct virtio_scsi *vscsi,
>> + struct
>> virtio_scsi_event *event)
>> +{
>> + struct scsi_device *sdev;
>> + struct Scsi_Host *shost = virtio_scsi_host(vscsi->vdev);
>> + unsigned int target = event->lun[1];
>> + unsigned int lun = (event->lun[2] << 8) | event->lun[3];
>> +
>> + switch (event->reason) {
>> + case VIRTIO_SCSI_EVT_RESET_RESCAN:
>> + scsi_add_device(shost, 0, target, lun);
>> + break;
>> + case VIRTIO_SCSI_EVT_RESET_REMOVED:
>> + sdev = scsi_device_lookup(shost, 0, target, lun);
>> + if (sdev) {
>> + scsi_remove_device(sdev);
>> + scsi_device_put(sdev);
>> + } else {
>> + pr_err("SCSI device %d 0 %d %d not found\n",
>> + shost->host_no, target, lun);
>> + }
>> + break;
>> + default:
>> + pr_info("Unsupport virtio scsi event reason %x\n", event->reason);
>> + }
>> +}
>> +
>> +static void virtscsi_handle_event(struct work_struct *work)
>> +{
>> + struct virtio_scsi_event_node *event_node =
>> + container_of(work, struct virtio_scsi_event_node, work);
>> + struct virtio_scsi *vscsi = event_node->vscsi;
>> + struct virtio_scsi_event *event = &event_node->event;
>> +
>> + switch (event->event) {
>> + case VIRTIO_SCSI_T_TRANSPORT_RESET:
>> + virtscsi_handle_transport_reset(vscsi, event);
>> + break;
>
> Please handle VIRTIO_SCSI_T_NO_EVENT too here, and mask out
> VIRTIO_SCSI_T_EVENTS_MISSED even if you do not handle it by triggering a
> full rescan.
>
Paolo, what's the appropriate action to response VIRTIO_SCSI_T_NO_EVENT
event? An error message?
I also have some confusion on VIRTIO_SCSI_T_EVENTS_MISSED:
Should VIRTIO_SCSI_T_EVENTS_MISSED always be used with other event flag?
For instanse:
(VIRTIO_SCSI_T_EVENTS_MISSED|VIRTIO_SCSI_T_TRANSPORT_RESET) is used to report
hotplug event dropped when a buffer available.
Thanks.
Cong.
> Paolo
>
>> + default:
>> + pr_err("Unsupport virtio scsi event %x\n", event->event);
>
>
>> + }
>> + virtscsi_kick_event(vscsi, event_node);
>> +}
>> +
>> +static void virtscsi_complete_event(void *buf)
>> +{
>> + struct virtio_scsi_event_node *event_node = buf;
>> +
>> + INIT_WORK(&event_node->work, virtscsi_handle_event);
>> + schedule_work(&event_node->work);
>> +}
>> +
>> static void virtscsi_event_done(struct virtqueue *vq)
>> {
>> - virtscsi_vq_done(vq, virtscsi_complete_free);
>> + virtscsi_vq_done(vq, virtscsi_complete_event);
>> };
>>
>> static void virtscsi_map_sgl(struct scatterlist *sg, unsigned int *p_idx,
>> @@ -435,6 +529,11 @@ static int virtscsi_init(struct virtio_device *vdev,
>>
>> virtscsi_config_set(vdev, cdb_size, VIRTIO_SCSI_CDB_SIZE);
>> virtscsi_config_set(vdev, sense_size, VIRTIO_SCSI_SENSE_SIZE);
>> +
>> + if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG)) {
>> + virtscsi_kick_event_all(vscsi);
>> + }
>> +
>> return 0;
>> }
>>
>> @@ -532,7 +631,13 @@ static struct virtio_device_id id_table[] = {
>> { 0 },
>> };
>>
>> +static unsigned int features[] = {
>> + VIRTIO_SCSI_F_HOTPLUG
>> +};
>> +
>> static struct virtio_driver virtio_scsi_driver = {
>> + .feature_table = features,
>> + .feature_table_size = ARRAY_SIZE(features),
>> .driver.name = KBUILD_MODNAME,
>> .driver.owner = THIS_MODULE,
>> .id_table = id_table,
>> diff --git a/include/linux/virtio_scsi.h b/include/linux/virtio_scsi.h
>> index 8ddeafd..dc8d305 100644
>> --- a/include/linux/virtio_scsi.h
>> +++ b/include/linux/virtio_scsi.h
>> @@ -69,6 +69,10 @@ struct virtio_scsi_config {
>> u32 max_lun;
>> } __packed;
>>
>> +/* Feature Bits */
>> +#define VIRTIO_SCSI_F_INOUT 0
>> +#define VIRTIO_SCSI_F_HOTPLUG 1
>> +
>> /* Response codes */
>> #define VIRTIO_SCSI_S_OK 0
>> #define VIRTIO_SCSI_S_OVERRUN 1
>> @@ -105,6 +109,11 @@ struct virtio_scsi_config {
>> #define VIRTIO_SCSI_T_TRANSPORT_RESET 1
>> #define VIRTIO_SCSI_T_ASYNC_NOTIFY 2
>>
>> +/* Reasons of transport reset event */
>> +#define VIRTIO_SCSI_EVT_RESET_HARD 0
>> +#define VIRTIO_SCSI_EVT_RESET_RESCAN 1
>> +#define VIRTIO_SCSI_EVT_RESET_REMOVED 2
>> +
>> #define VIRTIO_SCSI_S_SIMPLE 0
>> #define VIRTIO_SCSI_S_ORDERED 1
>> #define VIRTIO_SCSI_S_HEAD 2
>>
>
> Thanks,
>
> Paolo
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [PATCH] virtio-scsi: hotplug suppot for virtio-scsi
2012-07-02 7:20 ` mc
@ 2012-07-02 8:11 ` Paolo Bonzini
0 siblings, 0 replies; 4+ messages in thread
From: Paolo Bonzini @ 2012-07-02 8:11 UTC (permalink / raw)
To: mc
Cc: Rusty Russell, Nicholas A. Bellinger, stefanha, linuxram,
Anthony Liguori, senwang, zwanp, James E.J. Bottomley,
virtualization, linux-kernel, linux-scsi
Il 02/07/2012 09:20, mc@linux.vnet.ibm.com ha scritto:
>>> +static void virtscsi_handle_event(struct work_struct *work)
>>> +{
>>> + struct virtio_scsi_event_node *event_node =
>>> + container_of(work, struct virtio_scsi_event_node, work);
>>> + struct virtio_scsi *vscsi = event_node->vscsi;
>>> + struct virtio_scsi_event *event = &event_node->event;
>>> +
>>> + switch (event->event) {
>>> + case VIRTIO_SCSI_T_TRANSPORT_RESET:
>>> + virtscsi_handle_transport_reset(vscsi, event);
>>> + break;
>>
>> Please handle VIRTIO_SCSI_T_NO_EVENT too here, and mask out
>> VIRTIO_SCSI_T_EVENTS_MISSED even if you do not handle it by triggering a
>> full rescan.
>>
> Paolo, what's the appropriate action to response VIRTIO_SCSI_T_NO_EVENT
> event? An error message?
No, just do nothing.
> I also have some confusion on VIRTIO_SCSI_T_EVENTS_MISSED:
> Should VIRTIO_SCSI_T_EVENTS_MISSED always be used with other event flag?
Yes.
> For instanse:
> (VIRTIO_SCSI_T_EVENTS_MISSED|VIRTIO_SCSI_T_TRANSPORT_RESET) is used to
> report hotplug event dropped when a buffer available.
The idea in the spec was that QEMU would report VIRTIO_SCSI_T_NO_EVENT |
VIRTIO_SCSI_T_EVENTS_MISSED as soon as a buffer becomes available, but
technically this is indeed possible. So you need to handle
VIRTIO_SCSI_T_EVENTS_MISSED first, and the other bits separately.
Paolo
^ permalink raw reply [flat|nested] 4+ messages in thread
end of thread, other threads:[~2012-07-02 8:12 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2012-06-20 6:55 [PATCH] virtio-scsi: hotplug suppot for virtio-scsi Cong Meng
2012-07-01 13:24 ` Paolo Bonzini
2012-07-02 7:20 ` mc
2012-07-02 8:11 ` Paolo Bonzini
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).