linux-stable/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c
Thomas Gleixner d86a6d47bc bus: fsl-mc: fsl-mc-allocator: Rework MSI handling
Storing a pointer to the MSI descriptor just to track the Linux interrupt
number is daft. Just store the interrupt number and be done with it.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Link: https://lore.kernel.org/r/20211210221815.207838579@linutronix.de
2021-12-16 22:16:41 +01:00

194 lines
4.1 KiB
C

// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
/*
* Copyright 2013-2016 Freescale Semiconductor Inc.
* Copyright 2019 NXP
*/
#include <linux/vfio.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/eventfd.h>
#include <linux/msi.h>
#include "linux/fsl/mc.h"
#include "vfio_fsl_mc_private.h"
static int vfio_fsl_mc_irqs_allocate(struct vfio_fsl_mc_device *vdev)
{
struct fsl_mc_device *mc_dev = vdev->mc_dev;
struct vfio_fsl_mc_irq *mc_irq;
int irq_count;
int ret, i;
/* Device does not support any interrupt */
if (mc_dev->obj_desc.irq_count == 0)
return 0;
/* interrupts were already allocated for this device */
if (vdev->mc_irqs)
return 0;
irq_count = mc_dev->obj_desc.irq_count;
mc_irq = kcalloc(irq_count, sizeof(*mc_irq), GFP_KERNEL);
if (!mc_irq)
return -ENOMEM;
/* Allocate IRQs */
ret = fsl_mc_allocate_irqs(mc_dev);
if (ret) {
kfree(mc_irq);
return ret;
}
for (i = 0; i < irq_count; i++) {
mc_irq[i].count = 1;
mc_irq[i].flags = VFIO_IRQ_INFO_EVENTFD;
}
vdev->mc_irqs = mc_irq;
return 0;
}
static irqreturn_t vfio_fsl_mc_irq_handler(int irq_num, void *arg)
{
struct vfio_fsl_mc_irq *mc_irq = (struct vfio_fsl_mc_irq *)arg;
eventfd_signal(mc_irq->trigger, 1);
return IRQ_HANDLED;
}
static int vfio_set_trigger(struct vfio_fsl_mc_device *vdev,
int index, int fd)
{
struct vfio_fsl_mc_irq *irq = &vdev->mc_irqs[index];
struct eventfd_ctx *trigger;
int hwirq;
int ret;
hwirq = vdev->mc_dev->irqs[index]->virq;
if (irq->trigger) {
free_irq(hwirq, irq);
kfree(irq->name);
eventfd_ctx_put(irq->trigger);
irq->trigger = NULL;
}
if (fd < 0) /* Disable only */
return 0;
irq->name = kasprintf(GFP_KERNEL, "vfio-irq[%d](%s)",
hwirq, dev_name(&vdev->mc_dev->dev));
if (!irq->name)
return -ENOMEM;
trigger = eventfd_ctx_fdget(fd);
if (IS_ERR(trigger)) {
kfree(irq->name);
return PTR_ERR(trigger);
}
irq->trigger = trigger;
ret = request_irq(hwirq, vfio_fsl_mc_irq_handler, 0,
irq->name, irq);
if (ret) {
kfree(irq->name);
eventfd_ctx_put(trigger);
irq->trigger = NULL;
return ret;
}
return 0;
}
static int vfio_fsl_mc_set_irq_trigger(struct vfio_fsl_mc_device *vdev,
unsigned int index, unsigned int start,
unsigned int count, u32 flags,
void *data)
{
struct fsl_mc_device *mc_dev = vdev->mc_dev;
int ret, hwirq;
struct vfio_fsl_mc_irq *irq;
struct device *cont_dev = fsl_mc_cont_dev(&mc_dev->dev);
struct fsl_mc_device *mc_cont = to_fsl_mc_device(cont_dev);
if (!count && (flags & VFIO_IRQ_SET_DATA_NONE))
return vfio_set_trigger(vdev, index, -1);
if (start != 0 || count != 1)
return -EINVAL;
mutex_lock(&vdev->vdev.dev_set->lock);
ret = fsl_mc_populate_irq_pool(mc_cont,
FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
if (ret)
goto unlock;
ret = vfio_fsl_mc_irqs_allocate(vdev);
if (ret)
goto unlock;
mutex_unlock(&vdev->vdev.dev_set->lock);
if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
s32 fd = *(s32 *)data;
return vfio_set_trigger(vdev, index, fd);
}
hwirq = vdev->mc_dev->irqs[index]->virq;
irq = &vdev->mc_irqs[index];
if (flags & VFIO_IRQ_SET_DATA_NONE) {
vfio_fsl_mc_irq_handler(hwirq, irq);
} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
u8 trigger = *(u8 *)data;
if (trigger)
vfio_fsl_mc_irq_handler(hwirq, irq);
}
return 0;
unlock:
mutex_unlock(&vdev->vdev.dev_set->lock);
return ret;
}
int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,
u32 flags, unsigned int index,
unsigned int start, unsigned int count,
void *data)
{
if (flags & VFIO_IRQ_SET_ACTION_TRIGGER)
return vfio_fsl_mc_set_irq_trigger(vdev, index, start,
count, flags, data);
else
return -EINVAL;
}
/* Free All IRQs for the given MC object */
void vfio_fsl_mc_irqs_cleanup(struct vfio_fsl_mc_device *vdev)
{
struct fsl_mc_device *mc_dev = vdev->mc_dev;
int irq_count = mc_dev->obj_desc.irq_count;
int i;
/*
* Device does not support any interrupt or the interrupts
* were not configured
*/
if (!vdev->mc_irqs)
return;
for (i = 0; i < irq_count; i++)
vfio_set_trigger(vdev, i, -1);
fsl_mc_free_irqs(mc_dev);
kfree(vdev->mc_irqs);
vdev->mc_irqs = NULL;
}