In order to take advantages of Paolo's multi-queue virito-scsi, we need
multi-target support in tcm_vhost first. Otherwise all the requests go
to one queue and other queues are idle.
This patch makes:
1. All the targets under the wwpn is seen and can be used by guest.
2. No need to pass the tpgt number in struct vhost_scsi_target to
tcm_vhost.ko. Only wwpn is needed.
3. We can always pass max_target = 255 to guest now, since we abort the
request who's target id does not exist.
Changes in v2:
- Handle non-contiguous tpgt
Changes in v3:
- Simplfy lock in vhost_scsi_set_endpoint
- Return -EEXIST when does not match
Signed-off-by: Asias He <asias at redhat.com>
---
drivers/vhost/tcm_vhost.c | 131 +++++++++++++++++++++++++++++-----------------
drivers/vhost/tcm_vhost.h | 4 +-
2 files changed, 85 insertions(+), 50 deletions(-)
diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c
index 704e4f6..81ecda5 100644
--- a/drivers/vhost/tcm_vhost.c
+++ b/drivers/vhost/tcm_vhost.c
@@ -59,8 +59,14 @@ enum {
VHOST_SCSI_VQ_IO = 2,
};
+#define VHOST_SCSI_MAX_TARGET 256
+
struct vhost_scsi {
- struct tcm_vhost_tpg *vs_tpg; /* Protected by vhost_scsi->dev.mutex */
+ /* Protected by vhost_scsi->dev.mutex */
+ struct tcm_vhost_tpg *vs_tpg[VHOST_SCSI_MAX_TARGET];
+ char vs_vhost_wwpn[TRANSPORT_IQN_LEN];
+ bool vs_endpoint;
+
struct vhost_dev dev;
struct vhost_virtqueue vqs[3];
@@ -564,10 +570,10 @@ static void vhost_scsi_handle_vq(struct vhost_scsi *vs)
u32 exp_data_len, data_first, data_num, data_direction;
unsigned out, in, i;
int head, ret;
+ u8 target;
/* Must use ioctl VHOST_SCSI_SET_ENDPOINT */
- tv_tpg = vs->vs_tpg;
- if (unlikely(!tv_tpg))
+ if (unlikely(!vs->vs_endpoint))
return;
mutex_lock(&vq->mutex);
@@ -635,6 +641,28 @@ static void vhost_scsi_handle_vq(struct vhost_scsi *vs)
break;
}
+ /* Extract the tpgt */
+ target = v_req.lun[1];
+ tv_tpg = vs->vs_tpg[target];
+
+ /* Target does not exist, fail the request */
+ if (unlikely(!tv_tpg)) {
+ struct virtio_scsi_cmd_resp __user *resp;
+ struct virtio_scsi_cmd_resp rsp;
+
+ memset(&rsp, 0, sizeof(rsp));
+ rsp.response = VIRTIO_SCSI_S_BAD_TARGET;
+ resp = vq->iov[out].iov_base;
+ ret = __copy_to_user(resp, &rsp, sizeof(rsp));
+ if (!ret)
+ vhost_add_used_and_signal(&vs->dev,
+ &vs->vqs[2], head, 0);
+ else
+ pr_err("Faulted on virtio_scsi_cmd_resp\n");
+
+ continue;
+ }
+
exp_data_len = 0;
for (i = 0; i < data_num; i++)
exp_data_len += vq->iov[data_first + i].iov_len;
@@ -743,7 +771,8 @@ static int vhost_scsi_set_endpoint(
{
struct tcm_vhost_tport *tv_tport;
struct tcm_vhost_tpg *tv_tpg;
- int index;
+ bool match = false;
+ int index, ret;
mutex_lock(&vs->dev.mutex);
/* Verify that ring has been setup correctly. */
@@ -754,7 +783,6 @@ static int vhost_scsi_set_endpoint(
return -EFAULT;
}
}
- mutex_unlock(&vs->dev.mutex);
mutex_lock(&tcm_vhost_mutex);
list_for_each_entry(tv_tpg, &tcm_vhost_list, tv_tpg_list) {
@@ -769,30 +797,33 @@ static int vhost_scsi_set_endpoint(
}
tv_tport = tv_tpg->tport;
- if (!strcmp(tv_tport->tport_name, t->vhost_wwpn) &&
- (tv_tpg->tport_tpgt == t->vhost_tpgt)) {
- tv_tpg->tv_tpg_vhost_count++;
- mutex_unlock(&tv_tpg->tv_tpg_mutex);
- mutex_unlock(&tcm_vhost_mutex);
-
- mutex_lock(&vs->dev.mutex);
- if (vs->vs_tpg) {
- mutex_unlock(&vs->dev.mutex);
- mutex_lock(&tv_tpg->tv_tpg_mutex);
- tv_tpg->tv_tpg_vhost_count--;
+ if (!strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
+ if (vs->vs_tpg[tv_tpg->tport_tpgt]) {
mutex_unlock(&tv_tpg->tv_tpg_mutex);
+ mutex_unlock(&tcm_vhost_mutex);
+ mutex_unlock(&vs->dev.mutex);
return -EEXIST;
}
-
- vs->vs_tpg = tv_tpg;
+ tv_tpg->tv_tpg_vhost_count++;
+ vs->vs_tpg[tv_tpg->tport_tpgt] = tv_tpg;
smp_mb__after_atomic_inc();
- mutex_unlock(&vs->dev.mutex);
- return 0;
+ match = true;
}
mutex_unlock(&tv_tpg->tv_tpg_mutex);
}
mutex_unlock(&tcm_vhost_mutex);
- return -EINVAL;
+
+ if (match) {
+ memcpy(vs->vs_vhost_wwpn, t->vhost_wwpn,
+ sizeof(vs->vs_vhost_wwpn));
+ vs->vs_endpoint = true;
+ ret = 0;
+ } else {
+ ret = -EEXIST;
+ }
+
+ mutex_unlock(&vs->dev.mutex);
+ return ret;
}
static int vhost_scsi_clear_endpoint(
@@ -801,7 +832,8 @@ static int vhost_scsi_clear_endpoint(
{
struct tcm_vhost_tport *tv_tport;
struct tcm_vhost_tpg *tv_tpg;
- int index, ret;
+ int index, ret, i;
+ u8 target;
mutex_lock(&vs->dev.mutex);
/* Verify that ring has been setup correctly. */
@@ -811,27 +843,32 @@ static int vhost_scsi_clear_endpoint(
goto err;
}
}
+ for (i = 0; i < VHOST_SCSI_MAX_TARGET; i++) {
+ target = i;
- if (!vs->vs_tpg) {
- ret = -ENODEV;
- goto err;
- }
- tv_tpg = vs->vs_tpg;
- tv_tport = tv_tpg->tport;
-
- if (strcmp(tv_tport->tport_name, t->vhost_wwpn) ||
- (tv_tpg->tport_tpgt != t->vhost_tpgt)) {
- pr_warn("tv_tport->tport_name: %s, tv_tpg->tport_tpgt: %hu"
- " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
- tv_tport->tport_name, tv_tpg->tport_tpgt,
- t->vhost_wwpn, t->vhost_tpgt);
- ret = -EINVAL;
- goto err;
+ tv_tpg = vs->vs_tpg[target];
+ if (!tv_tpg)
+ continue;
+
+ tv_tport = tv_tpg->tport;
+ if (!tv_tport) {
+ ret = -ENODEV;
+ goto err;
+ }
+
+ if (strcmp(tv_tport->tport_name, t->vhost_wwpn)) {
+ pr_warn("tv_tport->tport_name: %s, tv_tpg->tport_tpgt: %hu"
+ " does not match t->vhost_wwpn: %s, t->vhost_tpgt: %hu\n",
+ tv_tport->tport_name, tv_tpg->tport_tpgt,
+ t->vhost_wwpn, t->vhost_tpgt);
+ ret = -EINVAL;
+ goto err;
+ }
+ tv_tpg->tv_tpg_vhost_count--;
+ vs->vs_tpg[target] = NULL;
+ vs->vs_endpoint = false;
}
- tv_tpg->tv_tpg_vhost_count--;
- vs->vs_tpg = NULL;
mutex_unlock(&vs->dev.mutex);
-
return 0;
err:
@@ -866,16 +903,12 @@ static int vhost_scsi_open(struct inode *inode, struct
file *f)
static int vhost_scsi_release(struct inode *inode, struct file *f)
{
struct vhost_scsi *s = f->private_data;
+ struct vhost_scsi_target t;
- if (s->vs_tpg && s->vs_tpg->tport) {
- struct vhost_scsi_target backend;
-
- memcpy(backend.vhost_wwpn, s->vs_tpg->tport->tport_name,
- sizeof(backend.vhost_wwpn));
- backend.vhost_tpgt = s->vs_tpg->tport_tpgt;
- vhost_scsi_clear_endpoint(s, &backend);
- }
-
+ mutex_lock(&s->dev.mutex);
+ memcpy(t.vhost_wwpn, s->vs_vhost_wwpn, sizeof(t.vhost_wwpn));
+ mutex_unlock(&s->dev.mutex);
+ vhost_scsi_clear_endpoint(s, &t);
vhost_dev_stop(&s->dev);
vhost_dev_cleanup(&s->dev, false);
kfree(s);
diff --git a/drivers/vhost/tcm_vhost.h b/drivers/vhost/tcm_vhost.h
index 47ee80b..519a550 100644
--- a/drivers/vhost/tcm_vhost.h
+++ b/drivers/vhost/tcm_vhost.h
@@ -93,9 +93,11 @@ struct tcm_vhost_tport {
*
* ABI Rev 0: July 2012 version starting point for v3.6-rc merge candidate +
* RFC-v2 vhost-scsi userspace. Add GET_ABI_VERSION ioctl usage
+ * ABI Rev 1: January 2013. Ignore vhost_tpgt filed in struct
vhost_scsi_target.
+ * All the targets under vhost_wwpn can be seen and used by guset.
*/
-#define VHOST_SCSI_ABI_VERSION 0
+#define VHOST_SCSI_ABI_VERSION 1
struct vhost_scsi_target {
int abi_version;
--
1.8.1
