diff options
Diffstat (limited to 'drivers/vfio/cdx/intr.c')
| -rw-r--r-- | drivers/vfio/cdx/intr.c | 217 |
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); +} |