diff mbox

[V4,1/5] virtio-scsi: redo allocation of target data

Message ID 1362969842-9145-2-git-send-email-gaowanlong@cn.fujitsu.com (mailing list archive)
State New, archived
Headers show

Commit Message

Wanlong Gao March 11, 2013, 2:43 a.m. UTC
From: Paolo Bonzini <pbonzini@redhat.com>

virtio_scsi_target_state is now empty, but we will find new uses
for it in the next few patches.  However, dropping the sglist lets
us turn the array-of-pointers into a simple array, which simplifies
the allocation.

However, we do not leave the virtio_scsi_target_state structs in the
flexible array member at the end of struct virtio_scsi, because
we will place the virtqueues there in the next patches.

Cc: linux-scsi@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
---
 drivers/scsi/virtio_scsi.c | 45 ++++++++++++---------------------------------
 1 file changed, 12 insertions(+), 33 deletions(-)

Comments

Paolo Bonzini March 11, 2013, 11:31 a.m. UTC | #1
Il 11/03/2013 03:43, Wanlong Gao ha scritto:
> virtio_scsi_target_state is now empty, but we will find new uses
> for it in the next few patches.  However, dropping the sglist lets
> us turn the array-of-pointers into a simple array, which simplifies
> the allocation.
> 
> However, we do not leave the virtio_scsi_target_state structs in the
> flexible array member at the end of struct virtio_scsi, because
> we will place the virtqueues there in the next patches.

If you have to respin, consider improving the grammar:

virtio_scsi_target_state is now empty.  We will find new uses for it in
the next few patches, so this patch does not drop it completely.
However, having dropped the sglist flexible array member, we can turn
the tgt array-of-pointers into a simple array.  This simplifies the
allocation.

Even simpler would be to place the virtio_scsi_target_state structs in a
flexible array member at the end of struct virtio_scsi.  But we do not
do that, because we will place the virtqueues there in the next patches.

Paolo

> Cc: linux-scsi@vger.kernel.org
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>

--
To unsubscribe from this list: send the line "unsubscribe kvm" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Asias He March 19, 2013, 6:57 a.m. UTC | #2
On Mon, Mar 11, 2013 at 10:43:58AM +0800, Wanlong Gao wrote:
> From: Paolo Bonzini <pbonzini@redhat.com>
> 
> virtio_scsi_target_state is now empty, but we will find new uses
> for it in the next few patches.  However, dropping the sglist lets
> us turn the array-of-pointers into a simple array, which simplifies
> the allocation.
> 
> However, we do not leave the virtio_scsi_target_state structs in the
> flexible array member at the end of struct virtio_scsi, because
> we will place the virtqueues there in the next patches.
> 
> Cc: linux-scsi@vger.kernel.org
> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
> Signed-off-by: Wanlong Gao <gaowanlong@cn.fujitsu.com>
> ---
>  drivers/scsi/virtio_scsi.c | 45 ++++++++++++---------------------------------
>  1 file changed, 12 insertions(+), 33 deletions(-)
> 
> diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
> index 6307099..75ccde1 100644
> --- a/drivers/scsi/virtio_scsi.c
> +++ b/drivers/scsi/virtio_scsi.c
> @@ -76,7 +76,7 @@ struct virtio_scsi {
>  	/* Get some buffers ready for event vq */
>  	struct virtio_scsi_event_node event_list[VIRTIO_SCSI_EVENT_LEN];
>  
> -	struct virtio_scsi_target_state *tgt[];
> +	struct virtio_scsi_target_state *tgt;
>  };
>  
>  static struct kmem_cache *virtscsi_cmd_cache;
> @@ -568,18 +568,9 @@ static void virtscsi_init_vq(struct virtio_scsi_vq *virtscsi_vq,
>  	virtscsi_vq->vq = vq;
>  }
>  
> -static struct virtio_scsi_target_state *virtscsi_alloc_tgt(
> -	struct virtio_device *vdev, int sg_elems)
> +static void virtscsi_init_tgt(struct virtio_scsi_target_state *tgt)
>  {
> -	struct virtio_scsi_target_state *tgt;
> -	gfp_t gfp_mask = GFP_KERNEL;
> -
> -	tgt = kmalloc(sizeof(*tgt), gfp_mask);
> -	if (!tgt)
> -		return NULL;
> -
>  	spin_lock_init(&tgt->tgt_lock);
> -	return tgt;
>  }
>  
>  static void virtscsi_scan(struct virtio_device *vdev)
> @@ -593,17 +584,10 @@ static void virtscsi_remove_vqs(struct virtio_device *vdev)
>  {
>  	struct Scsi_Host *sh = virtio_scsi_host(vdev);
>  	struct virtio_scsi *vscsi = shost_priv(sh);
> -	u32 i, num_targets;
>  
>  	/* Stop all the virtqueues. */
>  	vdev->config->reset(vdev);
> -
> -	num_targets = sh->max_id;
> -	for (i = 0; i < num_targets; i++) {
> -		kfree(vscsi->tgt[i]);
> -		vscsi->tgt[i] = NULL;
> -	}
> -
> +	kfree(vscsi->tgt);
>  	vdev->config->del_vqs(vdev);
>  }
>  
> @@ -612,7 +596,7 @@ static int virtscsi_init(struct virtio_device *vdev,
>  {
>  	int err;
>  	struct virtqueue *vqs[3];
> -	u32 i, sg_elems;
> +	u32 i;
>  
>  	vq_callback_t *callbacks[] = {
>  		virtscsi_ctrl_done,
> @@ -640,16 +624,14 @@ static int virtscsi_init(struct virtio_device *vdev,
>  	if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
>  		virtscsi_kick_event_all(vscsi);
>  
> -	/* We need to know how many segments before we allocate.  */
> -	sg_elems = virtscsi_config_get(vdev, seg_max) ?: 1;

The drop of sg_elems does not belong to this patch. It should be done in
'virtio-scsi: use virtqueue_add_sgs for command buffers'.

> -	for (i = 0; i < num_targets; i++) {
> -		vscsi->tgt[i] = virtscsi_alloc_tgt(vdev, sg_elems);
> -		if (!vscsi->tgt[i]) {
> -			err = -ENOMEM;
> -			goto out;
> -		}
> +	vscsi->tgt = kmalloc(num_targets * sizeof(vscsi->tgt[0]), GFP_KERNEL);
> +	if (!vscsi->tgt) {
> +		err = -ENOMEM;
> +		goto out;
>  	}
> +	for (i = 0; i < num_targets; i++)
> +		virtscsi_init_tgt(&vscsi->tgt[i]);
> +
>  	err = 0;
>  
>  out:
> @@ -668,10 +650,7 @@ static int virtscsi_probe(struct virtio_device *vdev)
>  
>  	/* Allocate memory and link the structs together.  */
>  	num_targets = virtscsi_config_get(vdev, max_target) + 1;
> -	shost = scsi_host_alloc(&virtscsi_host_template,
> -		sizeof(*vscsi)
> -		+ num_targets * sizeof(struct virtio_scsi_target_state));
> -
> +	shost = scsi_host_alloc(&virtscsi_host_template, sizeof(*vscsi));
>  	if (!shost)
>  		return -ENOMEM;
>  
> -- 
> 1.8.2.rc2
>
diff mbox

Patch

diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index 6307099..75ccde1 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c
@@ -76,7 +76,7 @@  struct virtio_scsi {
 	/* Get some buffers ready for event vq */
 	struct virtio_scsi_event_node event_list[VIRTIO_SCSI_EVENT_LEN];
 
-	struct virtio_scsi_target_state *tgt[];
+	struct virtio_scsi_target_state *tgt;
 };
 
 static struct kmem_cache *virtscsi_cmd_cache;
@@ -568,18 +568,9 @@  static void virtscsi_init_vq(struct virtio_scsi_vq *virtscsi_vq,
 	virtscsi_vq->vq = vq;
 }
 
-static struct virtio_scsi_target_state *virtscsi_alloc_tgt(
-	struct virtio_device *vdev, int sg_elems)
+static void virtscsi_init_tgt(struct virtio_scsi_target_state *tgt)
 {
-	struct virtio_scsi_target_state *tgt;
-	gfp_t gfp_mask = GFP_KERNEL;
-
-	tgt = kmalloc(sizeof(*tgt), gfp_mask);
-	if (!tgt)
-		return NULL;
-
 	spin_lock_init(&tgt->tgt_lock);
-	return tgt;
 }
 
 static void virtscsi_scan(struct virtio_device *vdev)
@@ -593,17 +584,10 @@  static void virtscsi_remove_vqs(struct virtio_device *vdev)
 {
 	struct Scsi_Host *sh = virtio_scsi_host(vdev);
 	struct virtio_scsi *vscsi = shost_priv(sh);
-	u32 i, num_targets;
 
 	/* Stop all the virtqueues. */
 	vdev->config->reset(vdev);
-
-	num_targets = sh->max_id;
-	for (i = 0; i < num_targets; i++) {
-		kfree(vscsi->tgt[i]);
-		vscsi->tgt[i] = NULL;
-	}
-
+	kfree(vscsi->tgt);
 	vdev->config->del_vqs(vdev);
 }
 
@@ -612,7 +596,7 @@  static int virtscsi_init(struct virtio_device *vdev,
 {
 	int err;
 	struct virtqueue *vqs[3];
-	u32 i, sg_elems;
+	u32 i;
 
 	vq_callback_t *callbacks[] = {
 		virtscsi_ctrl_done,
@@ -640,16 +624,14 @@  static int virtscsi_init(struct virtio_device *vdev,
 	if (virtio_has_feature(vdev, VIRTIO_SCSI_F_HOTPLUG))
 		virtscsi_kick_event_all(vscsi);
 
-	/* We need to know how many segments before we allocate.  */
-	sg_elems = virtscsi_config_get(vdev, seg_max) ?: 1;
-
-	for (i = 0; i < num_targets; i++) {
-		vscsi->tgt[i] = virtscsi_alloc_tgt(vdev, sg_elems);
-		if (!vscsi->tgt[i]) {
-			err = -ENOMEM;
-			goto out;
-		}
+	vscsi->tgt = kmalloc(num_targets * sizeof(vscsi->tgt[0]), GFP_KERNEL);
+	if (!vscsi->tgt) {
+		err = -ENOMEM;
+		goto out;
 	}
+	for (i = 0; i < num_targets; i++)
+		virtscsi_init_tgt(&vscsi->tgt[i]);
+
 	err = 0;
 
 out:
@@ -668,10 +650,7 @@  static int virtscsi_probe(struct virtio_device *vdev)
 
 	/* Allocate memory and link the structs together.  */
 	num_targets = virtscsi_config_get(vdev, max_target) + 1;
-	shost = scsi_host_alloc(&virtscsi_host_template,
-		sizeof(*vscsi)
-		+ num_targets * sizeof(struct virtio_scsi_target_state));
-
+	shost = scsi_host_alloc(&virtscsi_host_template, sizeof(*vscsi));
 	if (!shost)
 		return -ENOMEM;