[PATCH RFC 12/15] dmaengine: idxd: add device support functions in prep for mdev

Dave Jiang
2020-04-21T23:35:07Z

Add some device support helper functions that will be used by VFIO mediated
device in preparation of adding VFIO mdev support.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
---
drivers/dma/idxd/device.c | 130 +++++++++++++++++++++++++++++++++++++++++++++
drivers/dma/idxd/idxd.h | 7 ++
drivers/dma/idxd/init.c | 19 +++++++
3 files changed, 156 insertions(+)

diff --git a/drivers/dma/idxd/device.c b/drivers/dma/idxd/device.c
index a46b6558984c..830aa5859646 100644
--- a/drivers/dma/idxd/device.c
+++ b/drivers/dma/idxd/device.c
@@ -319,6 +319,40 @@ void idxd_wq_unmap_portal(struct idxd_wq *wq)
devm_iounmap(dev, wq->portal);
}

+int idxd_wq_abort(struct idxd_wq *wq)
+{
+ int rc;
+ struct idxd_device *idxd = wq->idxd;
+ struct device *dev = &idxd->pdev->dev;
+ u32 operand, status;
+
+ lockdep_assert_held(&idxd->dev_lock);
+
+ dev_dbg(dev, "Abort WQ %d\n", wq->id);
+ if (wq->state != IDXD_WQ_ENABLED) {
+ dev_dbg(dev, "WQ %d not active\n", wq->id);
+ return -ENXIO;
+ }
+
+ operand = BIT(wq->id % 16) | ((wq->id / 16) << 16);
+ dev_dbg(dev, "cmd: %u operand: %#x\n", IDXD_CMD_ABORT_WQ, operand);
+ rc = idxd_cmd_send(idxd, IDXD_CMD_ABORT_WQ, operand);
+ if (rc < 0)
+ return rc;
+
+ rc = idxd_cmd_wait(idxd, &status, IDXD_DRAIN_TIMEOUT);
+ if (rc < 0)
+ return rc;
+
+ if (status != IDXD_CMDSTS_SUCCESS) {
+ dev_dbg(dev, "WQ abort failed: %#x\n", status);
+ return -ENXIO;
+ }
+
+ dev_dbg(dev, "WQ %d aborted\n", wq->id);
+ return 0;
+}
+
int idxd_wq_set_pasid(struct idxd_wq *wq, int pasid)
{
struct idxd_device *idxd = wq->idxd;
@@ -372,6 +406,66 @@ int idxd_wq_disable_pasid(struct idxd_wq *wq)
return 0;
}

+void idxd_wq_update_pasid(struct idxd_wq *wq, int pasid)
+{
+ struct idxd_device *idxd = wq->idxd;
+ int offset;
+
+ lockdep_assert_held(&idxd->dev_lock);
+
+ /* PASID fields are 8 bytes into the WQCFG register */
+ offset = idxd->wqcfg_offset + wq->id * 32 + 8;
+ wq->wqcfg.pasid = pasid;
+ iowrite32(wq->wqcfg.bits[2], idxd->reg_base + offset);
+}
+
+void idxd_wq_update_priv(struct idxd_wq *wq, int priv)
+{
+ struct idxd_device *idxd = wq->idxd;
+ int offset;
+
+ lockdep_assert_held(&idxd->dev_lock);
+
+ /* priv field is 8 bytes into the WQCFG register */
+ offset = idxd->wqcfg_offset + wq->id * 32 + 8;
+ wq->wqcfg.priv = !!priv;
+ iowrite32(wq->wqcfg.bits[2], idxd->reg_base + offset);
+}
+
+int idxd_wq_drain(struct idxd_wq *wq)
+{
+ int rc;
+ struct idxd_device *idxd = wq->idxd;
+ struct device *dev = &idxd->pdev->dev;
+ u32 operand, status;
+
+ lockdep_assert_held(&idxd->dev_lock);
+
+ dev_dbg(dev, "Drain WQ %d\n", wq->id);
+ if (wq->state != IDXD_WQ_ENABLED) {
+ dev_dbg(dev, "WQ %d not active\n", wq->id);
+ return -ENXIO;
+ }
+
+ operand = BIT(wq->id % 16) | ((wq->id / 16) << 16);
+ dev_dbg(dev, "cmd: %u operand: %#x\n", IDXD_CMD_DRAIN_WQ, operand);
+ rc = idxd_cmd_send(idxd, IDXD_CMD_DRAIN_WQ, operand);
+ if (rc < 0)
+ return rc;
+
+ rc = idxd_cmd_wait(idxd, &status, IDXD_DRAIN_TIMEOUT);
+ if (rc < 0)
+ return rc;
+
+ if (status != IDXD_CMDSTS_SUCCESS) {
+ dev_dbg(dev, "WQ drain failed: %#x\n", status);
+ return -ENXIO;
+ }
+
+ dev_dbg(dev, "WQ %d drained\n", wq->id);
+ return 0;
+}
+
/* Device control bits */
static inline bool idxd_is_enabled(struct idxd_device *idxd)
{
@@ -542,6 +636,42 @@ int idxd_device_drain_pasid(struct idxd_device *idxd, int pasid)
return 0;
}

+int idxd_device_request_int_handle(struct idxd_device *idxd, int idx,
+ int *handle)
+{
+ int rc;
+ struct device *dev = &idxd->pdev->dev;
+ u32 operand, status;
+
+ lockdep_assert_held(&idxd->dev_lock);
+
+ if (!idxd->hw.gen_cap.int_handle_req)
+ return -EOPNOTSUPP;
+
+ dev_dbg(dev, "get int handle, idx %d\n", idx);
+
+ operand = idx & 0xffff;
+ dev_dbg(dev, "cmd: %u operand: %#x\n",
+ IDXD_CMD_REQUEST_INT_HANDLE, operand);
+ rc = idxd_cmd_send(idxd, IDXD_CMD_REQUEST_INT_HANDLE, operand);
+ if (rc < 0)
+ return rc;
+
+ rc = idxd_cmd_wait(idxd, &status, IDXD_REG_TIMEOUT);
+ if (rc < 0)
+ return rc;
+
+ if (status != IDXD_CMDSTS_SUCCESS) {
+ dev_dbg(dev, "request int handle failed: %#x\n", status);
+ return -ENXIO;
+ }
+
+ *handle = (status >> 8) & 0xffff;
+
+ dev_dbg(dev, "int handle acquired: %u\n", *handle);
+ return 0;
+}
+
/* Device configuration bits */
static void idxd_group_config_write(struct idxd_group *group)
{
diff --git a/drivers/dma/idxd/idxd.h b/drivers/dma/idxd/idxd.h
index 3a942e9c5980..9b56a4c7f3fc 100644
--- a/drivers/dma/idxd/idxd.h
+++ b/drivers/dma/idxd/idxd.h
@@ -199,6 +199,7 @@ struct idxd_device {

atomic_t num_allocated_ims;
struct sbitmap ims_sbmap;
+ int *int_handles;
};

/* IDXD software descriptor */
@@ -303,6 +304,8 @@ int idxd_device_ro_config(struct idxd_device *idxd);
void idxd_device_wqs_clear_state(struct idxd_device *idxd);
int idxd_device_drain_pasid(struct idxd_device *idxd, int pasid);
void idxd_device_load_config(struct idxd_device *idxd);
+int idxd_device_request_int_handle(struct idxd_device *idxd,
+ int idx, int *handle);

/* work queue control */
int idxd_wq_alloc_resources(struct idxd_wq *wq);
@@ -313,6 +316,10 @@ int idxd_wq_map_portal(struct idxd_wq *wq);
void idxd_wq_unmap_portal(struct idxd_wq *wq);
int idxd_wq_set_pasid(struct idxd_wq *wq, int pasid);
int idxd_wq_disable_pasid(struct idxd_wq *wq);
+int idxd_wq_abort(struct idxd_wq *wq);
+void idxd_wq_update_pasid(struct idxd_wq *wq, int pasid);
+void idxd_wq_update_priv(struct idxd_wq *wq, int priv);
+int idxd_wq_drain(struct idxd_wq *wq);

/* submission */
int idxd_submit_desc(struct idxd_wq *wq, struct idxd_desc *desc,
diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c
index 15b3ef73cac3..babe6e614087 100644
--- a/drivers/dma/idxd/init.c
+++ b/drivers/dma/idxd/init.c
@@ -56,6 +56,7 @@ static int idxd_setup_interrupts(struct idxd_device *idxd)
int i, msixcnt;
int rc = 0;
union msix_perm mperm;
+ unsigned long flags;

msixcnt = pci_msix_vec_count(pdev);
if (msixcnt < 0) {
@@ -130,6 +131,17 @@ static int idxd_setup_interrupts(struct idxd_device *idxd)
}
dev_dbg(dev, "Allocated idxd-msix %d for vector %d\n",
i, msix->vector);
+
+ if (idxd->hw.gen_cap.int_handle_req) {
+ spin_lock_irqsave(&idxd->dev_lock, flags);
+ rc = idxd_device_request_int_handle(idxd, i,
+ &idxd->int_handles[i]);
+ spin_unlock_irqrestore(&idxd->dev_lock, flags);
+ if (rc < 0)
+ goto err_no_irq;
+ dev_dbg(dev, "int handle requested: %u\n",
+ idxd->int_handles[i]);
+ }
}

idxd_unmask_error_interrupts(idxd);
@@ -168,6 +180,13 @@ static int idxd_setup_internals(struct idxd_device *idxd)
struct device *dev = &idxd->pdev->dev;
int i;

+ if (idxd->hw.gen_cap.int_handle_req) {
+ idxd->int_handles = devm_kcalloc(dev, idxd->max_wqs,
+ sizeof(int), GFP_KERNEL);
+ if (!idxd->int_handles)
+ return -ENOMEM;
+ }
+
idxd->groups = devm_kcalloc(dev, idxd->max_groups,
sizeof(struct idxd_group), GFP_KERNEL);
if (!idxd->groups)