[PATCH 3/5] virtio-scsi: allocate target pointers in a separate memory block
flat view
STALE5148d
From: Paolo Bonzini <pbonzini@redhat.com>
Date: 2012-08-28 11:55:11
Also in:
kvm, linux-scsi, lkml
Subsystem:
scsi subsystem, the rest, virtio block and scsi drivers · Maintainers:
"James E.J. Bottomley", "Martin K. Petersen", Linus Torvalds, "Michael S. Tsirkin", Jason Wang
We will place the request virtqueues in the flexible array member. Refining the virtqueue API would let us drop the sglist copy, at which point the pointer-to-array-of-pointers can become a simple pointer-to-array. It would both simplify the allocation and remove a dereference in several hot paths. Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> --- drivers/scsi/virtio_scsi.c | 23 +++++++++++++++-------- 1 files changed, 15 insertions(+), 8 deletions(-)
diff --git a/drivers/scsi/virtio_scsi.c b/drivers/scsi/virtio_scsi.c
index 595af1a..62fec04 100644
--- a/drivers/scsi/virtio_scsi.c
+++ b/drivers/scsi/virtio_scsi.c@@ -77,7 +77,7 @@ 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;
@@ -615,10 +615,13 @@ static void virtscsi_remove_vqs(struct virtio_device *vdev) /* 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; + if (vscsi->tgt) { + 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);
@@ -660,6 +663,12 @@ static int virtscsi_init(struct virtio_device *vdev, /* We need to know how many segments before we allocate. */ sg_elems = virtscsi_config_get(vdev, seg_max) ?: 1; + vscsi->tgt = kmalloc(num_targets * + sizeof(struct virtio_scsi_target_state *), GFP_KERNEL); + if (!vscsi->tgt) { + err = -ENOMEM; + goto out; + } for (i = 0; i < num_targets; i++) { vscsi->tgt[i] = virtscsi_alloc_tgt(vdev, sg_elems); if (!vscsi->tgt[i]) {
@@ -685,9 +694,7 @@ static int __devinit 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;
--
1.7.1