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Diffstat (limited to 'drivers/vfio/cdx/intr.c')
-rw-r--r--drivers/vfio/cdx/intr.c217
1 files changed, 217 insertions, 0 deletions
diff --git a/drivers/vfio/cdx/intr.c b/drivers/vfio/cdx/intr.c
new file mode 100644
index 0000000000..986fa2a45f
--- /dev/null
+++ b/drivers/vfio/cdx/intr.c
@@ -0,0 +1,217 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2022-2023, Advanced Micro Devices, Inc.
+ */
+
+#include <linux/vfio.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/eventfd.h>
+#include <linux/msi.h>
+#include <linux/interrupt.h>
+
+#include "linux/cdx/cdx_bus.h"
+#include "private.h"
+
+static irqreturn_t vfio_cdx_msihandler(int irq_no, void *arg)
+{
+ struct eventfd_ctx *trigger = arg;
+
+ eventfd_signal(trigger);
+ return IRQ_HANDLED;
+}
+
+static int vfio_cdx_msi_enable(struct vfio_cdx_device *vdev, int nvec)
+{
+ struct cdx_device *cdx_dev = to_cdx_device(vdev->vdev.dev);
+ struct device *dev = vdev->vdev.dev;
+ int msi_idx, ret;
+
+ vdev->cdx_irqs = kcalloc(nvec, sizeof(struct vfio_cdx_irq), GFP_KERNEL);
+ if (!vdev->cdx_irqs)
+ return -ENOMEM;
+
+ ret = cdx_enable_msi(cdx_dev);
+ if (ret) {
+ kfree(vdev->cdx_irqs);
+ return ret;
+ }
+
+ /* Allocate cdx MSIs */
+ ret = msi_domain_alloc_irqs(dev, MSI_DEFAULT_DOMAIN, nvec);
+ if (ret) {
+ cdx_disable_msi(cdx_dev);
+ kfree(vdev->cdx_irqs);
+ return ret;
+ }
+
+ for (msi_idx = 0; msi_idx < nvec; msi_idx++)
+ vdev->cdx_irqs[msi_idx].irq_no = msi_get_virq(dev, msi_idx);
+
+ vdev->msi_count = nvec;
+ vdev->config_msi = 1;
+
+ return 0;
+}
+
+static int vfio_cdx_msi_set_vector_signal(struct vfio_cdx_device *vdev,
+ int vector, int fd)
+{
+ struct eventfd_ctx *trigger;
+ int irq_no, ret;
+
+ if (vector < 0 || vector >= vdev->msi_count)
+ return -EINVAL;
+
+ irq_no = vdev->cdx_irqs[vector].irq_no;
+
+ if (vdev->cdx_irqs[vector].trigger) {
+ free_irq(irq_no, vdev->cdx_irqs[vector].trigger);
+ kfree(vdev->cdx_irqs[vector].name);
+ eventfd_ctx_put(vdev->cdx_irqs[vector].trigger);
+ vdev->cdx_irqs[vector].trigger = NULL;
+ }
+
+ if (fd < 0)
+ return 0;
+
+ vdev->cdx_irqs[vector].name = kasprintf(GFP_KERNEL, "vfio-msi[%d](%s)",
+ vector, dev_name(vdev->vdev.dev));
+ if (!vdev->cdx_irqs[vector].name)
+ return -ENOMEM;
+
+ trigger = eventfd_ctx_fdget(fd);
+ if (IS_ERR(trigger)) {
+ kfree(vdev->cdx_irqs[vector].name);
+ return PTR_ERR(trigger);
+ }
+
+ ret = request_irq(irq_no, vfio_cdx_msihandler, 0,
+ vdev->cdx_irqs[vector].name, trigger);
+ if (ret) {
+ kfree(vdev->cdx_irqs[vector].name);
+ eventfd_ctx_put(trigger);
+ return ret;
+ }
+
+ vdev->cdx_irqs[vector].trigger = trigger;
+
+ return 0;
+}
+
+static int vfio_cdx_msi_set_block(struct vfio_cdx_device *vdev,
+ unsigned int start, unsigned int count,
+ int32_t *fds)
+{
+ int i, j, ret = 0;
+
+ if (start >= vdev->msi_count || start + count > vdev->msi_count)
+ return -EINVAL;
+
+ for (i = 0, j = start; i < count && !ret; i++, j++) {
+ int fd = fds ? fds[i] : -1;
+
+ ret = vfio_cdx_msi_set_vector_signal(vdev, j, fd);
+ }
+
+ if (ret) {
+ for (--j; j >= (int)start; j--)
+ vfio_cdx_msi_set_vector_signal(vdev, j, -1);
+ }
+
+ return ret;
+}
+
+static void vfio_cdx_msi_disable(struct vfio_cdx_device *vdev)
+{
+ struct cdx_device *cdx_dev = to_cdx_device(vdev->vdev.dev);
+ struct device *dev = vdev->vdev.dev;
+
+ vfio_cdx_msi_set_block(vdev, 0, vdev->msi_count, NULL);
+
+ if (!vdev->config_msi)
+ return;
+
+ msi_domain_free_irqs_all(dev, MSI_DEFAULT_DOMAIN);
+ cdx_disable_msi(cdx_dev);
+ kfree(vdev->cdx_irqs);
+
+ vdev->cdx_irqs = NULL;
+ vdev->msi_count = 0;
+ vdev->config_msi = 0;
+}
+
+static int vfio_cdx_set_msi_trigger(struct vfio_cdx_device *vdev,
+ unsigned int index, unsigned int start,
+ unsigned int count, u32 flags,
+ void *data)
+{
+ struct cdx_device *cdx_dev = to_cdx_device(vdev->vdev.dev);
+ int i;
+
+ if (start + count > cdx_dev->num_msi)
+ return -EINVAL;
+
+ if (!count && (flags & VFIO_IRQ_SET_DATA_NONE)) {
+ vfio_cdx_msi_disable(vdev);
+ return 0;
+ }
+
+ if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
+ s32 *fds = data;
+ int ret;
+
+ if (vdev->config_msi)
+ return vfio_cdx_msi_set_block(vdev, start, count,
+ fds);
+ ret = vfio_cdx_msi_enable(vdev, cdx_dev->num_msi);
+ if (ret)
+ return ret;
+
+ ret = vfio_cdx_msi_set_block(vdev, start, count, fds);
+ if (ret)
+ vfio_cdx_msi_disable(vdev);
+
+ return ret;
+ }
+
+ for (i = start; i < start + count; i++) {
+ if (!vdev->cdx_irqs[i].trigger)
+ continue;
+ if (flags & VFIO_IRQ_SET_DATA_NONE) {
+ eventfd_signal(vdev->cdx_irqs[i].trigger);
+ } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
+ u8 *bools = data;
+
+ if (bools[i - start])
+ eventfd_signal(vdev->cdx_irqs[i].trigger);
+ }
+ }
+
+ return 0;
+}
+
+int vfio_cdx_set_irqs_ioctl(struct vfio_cdx_device *vdev,
+ u32 flags, unsigned int index,
+ unsigned int start, unsigned int count,
+ void *data)
+{
+ if (flags & VFIO_IRQ_SET_ACTION_TRIGGER)
+ return vfio_cdx_set_msi_trigger(vdev, index, start,
+ count, flags, data);
+ else
+ return -EINVAL;
+}
+
+/* Free All IRQs for the given device */
+void vfio_cdx_irqs_cleanup(struct vfio_cdx_device *vdev)
+{
+ /*
+ * Device does not support any interrupt or the interrupts
+ * were not configured
+ */
+ if (!vdev->cdx_irqs)
+ return;
+
+ vfio_cdx_set_msi_trigger(vdev, 0, 0, 0, VFIO_IRQ_SET_DATA_NONE, NULL);
+}