[PATCH v6 14/20] vfio/mdev: idxd: add 1dwq-v1 mdev type

Dave Jiang
2021-05-22T00:22:52Z

Add mdev device type "1dwq-v1" support code. 1dwq-v1 is defined as a
single DSA gen1 dedicated WQ. This WQ cannot be shared between guests. The
guest also cannot change any WQ configuration.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
drivers/vfio/mdev/idxd/mdev.c | 173 +++++++++++++++++++++++++++++++++++++++--
1 file changed, 166 insertions(+), 7 deletions(-)

diff --git a/drivers/vfio/mdev/idxd/mdev.c b/drivers/vfio/mdev/idxd/mdev.c
index e484095baeea..9f6c4997ec24 100644
--- a/drivers/vfio/mdev/idxd/mdev.c
+++ b/drivers/vfio/mdev/idxd/mdev.c
@@ -22,6 +22,13 @@
#include "idxd.h"
#include "mdev.h"

+static const char idxd_dsa_1dwq_name[] = "dsa-1dwq-v1";
+static const char idxd_iax_1dwq_name[] = "iax-1dwq-v1";
+
+static int idxd_vdcm_set_irqs(struct vdcm_idxd *vidxd, uint32_t flags,
+ unsigned int index, unsigned int start,
+ unsigned int count, void *data);
+
int idxd_mdev_get_pasid(struct mdev_device *mdev, struct vfio_device *vdev, u32 *pasid)
{
struct vfio_group *vfio_group = vdev->group;
@@ -41,10 +48,6 @@ int idxd_mdev_get_pasid(struct mdev_device *mdev, struct vfio_device *vdev, u32
return 0;
}

-static int idxd_vdcm_set_irqs(struct vdcm_idxd *vidxd, uint32_t flags,
- unsigned int index, unsigned int start,
- unsigned int count, void *data);
-
static int idxd_vdcm_get_irq_count(struct vfio_device *vdev, int type)
{
if (type == VFIO_PCI_MSIX_IRQ_INDEX)
@@ -53,18 +56,73 @@ static int idxd_vdcm_get_irq_count(struct vfio_device *vdev, int type)
return 0;
}

+static struct idxd_wq *find_any_dwq(struct idxd_device *idxd, struct vdcm_idxd_type *type)
+{
+ int i;
+ struct idxd_wq *wq;
+ unsigned long flags;
+
+ switch (type->type) {
+ case IDXD_MDEV_TYPE_DSA_1_DWQ:
+ if (idxd->data->type != IDXD_TYPE_DSA)
+ return NULL;
+ break;
+ case IDXD_MDEV_TYPE_IAX_1_DWQ:
+ if (idxd->data->type != IDXD_TYPE_IAX)
+ return NULL;
+ break;
+ default:
+ return NULL;
+ }
+
+ spin_lock_irqsave(&idxd->dev_lock, flags);
+ for (i = 0; i < idxd->max_wqs; i++) {
+ wq = idxd->wqs[i];
+
+ if (wq->state != IDXD_WQ_ENABLED)
+ continue;
+
+ if (!wq_dedicated(wq))
+ continue;
+
+ if (!is_idxd_wq_mdev(wq))
+ continue;
+
+ if (idxd_wq_refcount(wq) != 0)
+ continue;
+
+ spin_unlock_irqrestore(&idxd->dev_lock, flags);
+ mutex_lock(&wq->wq_lock);
+ if (idxd_wq_refcount(wq)) {
+ spin_lock_irqsave(&idxd->dev_lock, flags);
+ continue;
+ }
+
+ idxd_wq_get(wq);
+ mutex_unlock(&wq->wq_lock);
+ return wq;
+ }
+
+ spin_unlock_irqrestore(&idxd->dev_lock, flags);
+ return NULL;
+}
+
static struct vdcm_idxd *vdcm_vidxd_create(struct idxd_device *idxd, struct mdev_device *mdev,
struct vdcm_idxd_type *type)
{
struct vdcm_idxd *vidxd;
struct idxd_wq *wq = NULL;
+ int rc;

+ wq = find_any_dwq(idxd, type);
if (!wq)
return ERR_PTR(-ENODEV);

vidxd = kzalloc(sizeof(*vidxd), GFP_KERNEL);
- if (!vidxd)
- return ERR_PTR(-ENOMEM);
+ if (!vidxd) {
+ rc = -ENOMEM;
+ goto err;
+ }

mutex_init(&vidxd->dev_lock);
vidxd->idxd = idxd;
@@ -80,9 +138,24 @@ static struct vdcm_idxd *vdcm_vidxd_create(struct idxd_device *idxd, struct mdev
vidxd_init(vidxd);

return vidxd;
+
+ err:
+ mutex_lock(&wq->wq_lock);
+ idxd_wq_put(wq);
+ mutex_unlock(&wq->wq_lock);
+ return ERR_PTR(rc);
}

-static struct vdcm_idxd_type idxd_mdev_types[IDXD_MDEV_TYPES];
+static struct vdcm_idxd_type idxd_mdev_types[IDXD_MDEV_TYPES] = {
+ {
+ .name = idxd_dsa_1dwq_name,
+ .type = IDXD_MDEV_TYPE_DSA_1_DWQ,
+ },
+ {
+ .name = idxd_iax_1dwq_name,
+ .type = IDXD_MDEV_TYPE_IAX_1_DWQ,
+ },
+};

static struct vdcm_idxd_type *idxd_vdcm_get_type(struct mdev_device *mdev)
{
@@ -677,6 +750,91 @@ static const struct vfio_device_ops idxd_mdev_ops = {
.ioctl = idxd_vdcm_ioctl,
};

+static ssize_t name_show(struct mdev_type *mtype, struct mdev_type_attribute *attr, char *buf)
+{
+ return sysfs_emit(buf, "%s\n", idxd_mdev_types[mtype_get_type_group_id(mtype)].name);
+}
+static MDEV_TYPE_ATTR_RO(name);
+
+static int find_available_mdev_instances(struct idxd_device *idxd, struct vdcm_idxd_type *type)
+{
+ int count = 0, i;
+ unsigned long flags;
+
+ switch (type->type) {
+ case IDXD_MDEV_TYPE_DSA_1_DWQ:
+ if (idxd->data->type != IDXD_TYPE_DSA)
+ return 0;
+ break;
+ case IDXD_MDEV_TYPE_IAX_1_DWQ:
+ if (idxd->data->type != IDXD_TYPE_IAX)
+ return 0;
+ break;
+ default:
+ return 0;
+ }
+
+ spin_lock_irqsave(&idxd->dev_lock, flags);
+ for (i = 0; i < idxd->max_wqs; i++) {
+ struct idxd_wq *wq;
+
+ wq = idxd->wqs[i];
+ if (!is_idxd_wq_mdev(wq) || !wq_dedicated(wq) || idxd_wq_refcount(wq))
+ continue;
+
+ count++;
+ }
+ spin_unlock_irqrestore(&idxd->dev_lock, flags);
+
+ return count;
+}
+
+static ssize_t available_instances_show(struct mdev_type *mtype,
+ struct mdev_type_attribute *attr,
+ char *buf)
+{
+ struct device *dev = mtype_get_parent_dev(mtype);
+ struct idxd_device *idxd = dev_get_drvdata(dev);
+ int count;
+ struct vdcm_idxd_type *type;
+
+ type = &idxd_mdev_types[mtype_get_type_group_id(mtype)];
+ count = find_available_mdev_instances(idxd, type);
+
+ return sysfs_emit(buf, "%d\n", count);
+}
+static MDEV_TYPE_ATTR_RO(available_instances);
+
+static ssize_t device_api_show(struct mdev_type *mtype, struct mdev_type_attribute *attr,
+ char *buf)
+{
+ return sysfs_emit(buf, "%s\n", VFIO_DEVICE_API_PCI_STRING);
+}
+static MDEV_TYPE_ATTR_RO(device_api);
+
+static struct attribute *idxd_mdev_types_attrs[] = {
+ &mdev_type_attr_name.attr,
+ &mdev_type_attr_device_api.attr,
+ &mdev_type_attr_available_instances.attr,
+ NULL,
+};
+
+static struct attribute_group idxd_mdev_type_dsa_group0 = {
+ .name = idxd_dsa_1dwq_name,
+ .attrs = idxd_mdev_types_attrs,
+};
+
+static struct attribute_group idxd_mdev_type_iax_group0 = {
+ .name = idxd_iax_1dwq_name,
+ .attrs = idxd_mdev_types_attrs,
+};
+
+static struct attribute_group *idxd_mdev_type_groups[] = {
+ &idxd_mdev_type_dsa_group0,
+ &idxd_mdev_type_iax_group0,
+ NULL,
+};
+
static struct mdev_driver idxd_vdcm_driver = {
.driver = {
.name = "idxd-mdev",
@@ -685,6 +843,7 @@ static struct mdev_driver idxd_vdcm_driver = {
},
.probe = idxd_vdcm_probe,
.remove = idxd_vdcm_remove,
+ .supported_type_groups = idxd_mdev_type_groups,
};

static int idxd_mdev_drv_probe(struct device *dev)