[PATCH v5 12/14] vfio/mdev: idxd: add irq bypass for IMS vectors

[Dave Jiang]

Add support to bypass host for IMS interrupts configured for the guest.

Signed-off-by: Dave Jiang <dave.ji...@intel.com>
---
 drivers/vfio/mdev/Kconfig     |    1 +
 drivers/vfio/mdev/idxd/mdev.c |   17 +++++++++++++++--
 drivers/vfio/mdev/idxd/mdev.h |    1 +
 3 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/drivers/vfio/mdev/Kconfig b/drivers/vfio/mdev/Kconfig
index e9540e43d1f1..ab0a6f0930bc 100644
--- a/drivers/vfio/mdev/Kconfig
+++ b/drivers/vfio/mdev/Kconfig
@@ -22,6 +22,7 @@ config VFIO_MDEV_IDXD
        depends on VFIO && VFIO_MDEV && X86_64
        select AUXILIARY_BUS
        select IMS_MSI_ARRAY
+       select IRQ_BYPASS_MANAGER
        default n
        help
          VFIO based mediated device driver for Intel Accelerator Devices 
driver.
diff --git a/drivers/vfio/mdev/idxd/mdev.c b/drivers/vfio/mdev/idxd/mdev.c
index 8a4af882a47f..d59920f78109 100644
--- a/drivers/vfio/mdev/idxd/mdev.c
+++ b/drivers/vfio/mdev/idxd/mdev.c
@@ -616,9 +616,13 @@ static int msix_trigger_unregister(struct vdcm_idxd 
*vidxd, int index)
 
        dev_dbg(dev, "disable MSIX trigger %d\n", index);
        if (index) {
+               struct irq_bypass_producer *producer;
                u32 auxval;
 
+               producer = &vidxd->vdev.producer[index];
+               irq_bypass_unregister_producer(producer);
                irq_entry = &vidxd->irq_entries[index];
+
                if (irq_entry->irq_set) {
                        free_irq(irq_entry->irq, irq_entry);
                        irq_entry->irq_set = false;
@@ -654,9 +658,10 @@ static int msix_trigger_register(struct vdcm_idxd *vidxd, 
u32 fd, int index)
        }
 
        if (index) {
-               u32 pasid;
-               u32 auxval;
+               struct irq_bypass_producer *producer;
+               u32 pasid, auxval;
 
+               producer = &vidxd->vdev.producer[index];
                irq_entry = &vidxd->irq_entries[index];
                rc = idxd_mdev_get_pasid(mdev, &pasid);
                if (rc < 0)
@@ -682,6 +687,14 @@ static int msix_trigger_register(struct vdcm_idxd *vidxd, 
u32 fd, int index)
                        irq_set_auxdata(irq_entry->irq, 
IMS_AUXDATA_CONTROL_WORD, auxval);
                        return rc;
                }
+
+               producer->token = trigger;
+               producer->irq = irq_entry->irq;
+               rc = irq_bypass_register_producer(producer);
+               if (unlikely(rc))
+                       dev_info(dev, "irq bypass producer (token %p) 
registration failed: %d\n",
+                                producer->token, rc);
+
                irq_entry->irq_set = true;
        }
 
diff --git a/drivers/vfio/mdev/idxd/mdev.h b/drivers/vfio/mdev/idxd/mdev.h
index 8421b4962ac7..1f867de416e7 100644
--- a/drivers/vfio/mdev/idxd/mdev.h
+++ b/drivers/vfio/mdev/idxd/mdev.h
@@ -45,6 +45,7 @@ struct idxd_vdev {
        struct mdev_device *mdev;
        struct vfio_group *vfio_group;
        struct eventfd_ctx *msix_trigger[VIDXD_MAX_MSIX_ENTRIES];
+       struct irq_bypass_producer producer[VIDXD_MAX_MSIX_ENTRIES];
 };
 
 struct vdcm_idxd {