linux/drivers/vfio/platform/vfio_platform_irq.c
Thomas Gleixner 1802d0beec treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 174
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 655 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070034.575739538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:41 -07:00

330 lines
6.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* VFIO platform devices interrupt handling
*
* Copyright (C) 2013 - Virtual Open Systems
* Author: Antonios Motakis <a.motakis@virtualopensystems.com>
*/
#include <linux/eventfd.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
#include <linux/types.h>
#include <linux/vfio.h>
#include <linux/irq.h>
#include "vfio_platform_private.h"
static void vfio_platform_mask(struct vfio_platform_irq *irq_ctx)
{
unsigned long flags;
spin_lock_irqsave(&irq_ctx->lock, flags);
if (!irq_ctx->masked) {
disable_irq_nosync(irq_ctx->hwirq);
irq_ctx->masked = true;
}
spin_unlock_irqrestore(&irq_ctx->lock, flags);
}
static int vfio_platform_mask_handler(void *opaque, void *unused)
{
struct vfio_platform_irq *irq_ctx = opaque;
vfio_platform_mask(irq_ctx);
return 0;
}
static int vfio_platform_set_irq_mask(struct vfio_platform_device *vdev,
unsigned index, unsigned start,
unsigned count, uint32_t flags,
void *data)
{
if (start != 0 || count != 1)
return -EINVAL;
if (!(vdev->irqs[index].flags & VFIO_IRQ_INFO_MASKABLE))
return -EINVAL;
if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
int32_t fd = *(int32_t *)data;
if (fd >= 0)
return vfio_virqfd_enable((void *) &vdev->irqs[index],
vfio_platform_mask_handler,
NULL, NULL,
&vdev->irqs[index].mask, fd);
vfio_virqfd_disable(&vdev->irqs[index].mask);
return 0;
}
if (flags & VFIO_IRQ_SET_DATA_NONE) {
vfio_platform_mask(&vdev->irqs[index]);
} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
uint8_t mask = *(uint8_t *)data;
if (mask)
vfio_platform_mask(&vdev->irqs[index]);
}
return 0;
}
static void vfio_platform_unmask(struct vfio_platform_irq *irq_ctx)
{
unsigned long flags;
spin_lock_irqsave(&irq_ctx->lock, flags);
if (irq_ctx->masked) {
enable_irq(irq_ctx->hwirq);
irq_ctx->masked = false;
}
spin_unlock_irqrestore(&irq_ctx->lock, flags);
}
static int vfio_platform_unmask_handler(void *opaque, void *unused)
{
struct vfio_platform_irq *irq_ctx = opaque;
vfio_platform_unmask(irq_ctx);
return 0;
}
static int vfio_platform_set_irq_unmask(struct vfio_platform_device *vdev,
unsigned index, unsigned start,
unsigned count, uint32_t flags,
void *data)
{
if (start != 0 || count != 1)
return -EINVAL;
if (!(vdev->irqs[index].flags & VFIO_IRQ_INFO_MASKABLE))
return -EINVAL;
if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
int32_t fd = *(int32_t *)data;
if (fd >= 0)
return vfio_virqfd_enable((void *) &vdev->irqs[index],
vfio_platform_unmask_handler,
NULL, NULL,
&vdev->irqs[index].unmask,
fd);
vfio_virqfd_disable(&vdev->irqs[index].unmask);
return 0;
}
if (flags & VFIO_IRQ_SET_DATA_NONE) {
vfio_platform_unmask(&vdev->irqs[index]);
} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
uint8_t unmask = *(uint8_t *)data;
if (unmask)
vfio_platform_unmask(&vdev->irqs[index]);
}
return 0;
}
static irqreturn_t vfio_automasked_irq_handler(int irq, void *dev_id)
{
struct vfio_platform_irq *irq_ctx = dev_id;
unsigned long flags;
int ret = IRQ_NONE;
spin_lock_irqsave(&irq_ctx->lock, flags);
if (!irq_ctx->masked) {
ret = IRQ_HANDLED;
/* automask maskable interrupts */
disable_irq_nosync(irq_ctx->hwirq);
irq_ctx->masked = true;
}
spin_unlock_irqrestore(&irq_ctx->lock, flags);
if (ret == IRQ_HANDLED)
eventfd_signal(irq_ctx->trigger, 1);
return ret;
}
static irqreturn_t vfio_irq_handler(int irq, void *dev_id)
{
struct vfio_platform_irq *irq_ctx = dev_id;
eventfd_signal(irq_ctx->trigger, 1);
return IRQ_HANDLED;
}
static int vfio_set_trigger(struct vfio_platform_device *vdev, int index,
int fd, irq_handler_t handler)
{
struct vfio_platform_irq *irq = &vdev->irqs[index];
struct eventfd_ctx *trigger;
int ret;
if (irq->trigger) {
irq_clear_status_flags(irq->hwirq, IRQ_NOAUTOEN);
free_irq(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)",
irq->hwirq, vdev->name);
if (!irq->name)
return -ENOMEM;
trigger = eventfd_ctx_fdget(fd);
if (IS_ERR(trigger)) {
kfree(irq->name);
return PTR_ERR(trigger);
}
irq->trigger = trigger;
irq_set_status_flags(irq->hwirq, IRQ_NOAUTOEN);
ret = request_irq(irq->hwirq, handler, 0, irq->name, irq);
if (ret) {
kfree(irq->name);
eventfd_ctx_put(trigger);
irq->trigger = NULL;
return ret;
}
if (!irq->masked)
enable_irq(irq->hwirq);
return 0;
}
static int vfio_platform_set_irq_trigger(struct vfio_platform_device *vdev,
unsigned index, unsigned start,
unsigned count, uint32_t flags,
void *data)
{
struct vfio_platform_irq *irq = &vdev->irqs[index];
irq_handler_t handler;
if (vdev->irqs[index].flags & VFIO_IRQ_INFO_AUTOMASKED)
handler = vfio_automasked_irq_handler;
else
handler = vfio_irq_handler;
if (!count && (flags & VFIO_IRQ_SET_DATA_NONE))
return vfio_set_trigger(vdev, index, -1, handler);
if (start != 0 || count != 1)
return -EINVAL;
if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
int32_t fd = *(int32_t *)data;
return vfio_set_trigger(vdev, index, fd, handler);
}
if (flags & VFIO_IRQ_SET_DATA_NONE) {
handler(irq->hwirq, irq);
} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
uint8_t trigger = *(uint8_t *)data;
if (trigger)
handler(irq->hwirq, irq);
}
return 0;
}
int vfio_platform_set_irqs_ioctl(struct vfio_platform_device *vdev,
uint32_t flags, unsigned index, unsigned start,
unsigned count, void *data)
{
int (*func)(struct vfio_platform_device *vdev, unsigned index,
unsigned start, unsigned count, uint32_t flags,
void *data) = NULL;
switch (flags & VFIO_IRQ_SET_ACTION_TYPE_MASK) {
case VFIO_IRQ_SET_ACTION_MASK:
func = vfio_platform_set_irq_mask;
break;
case VFIO_IRQ_SET_ACTION_UNMASK:
func = vfio_platform_set_irq_unmask;
break;
case VFIO_IRQ_SET_ACTION_TRIGGER:
func = vfio_platform_set_irq_trigger;
break;
}
if (!func)
return -ENOTTY;
return func(vdev, index, start, count, flags, data);
}
int vfio_platform_irq_init(struct vfio_platform_device *vdev)
{
int cnt = 0, i;
while (vdev->get_irq(vdev, cnt) >= 0)
cnt++;
vdev->irqs = kcalloc(cnt, sizeof(struct vfio_platform_irq), GFP_KERNEL);
if (!vdev->irqs)
return -ENOMEM;
for (i = 0; i < cnt; i++) {
int hwirq = vdev->get_irq(vdev, i);
if (hwirq < 0)
goto err;
spin_lock_init(&vdev->irqs[i].lock);
vdev->irqs[i].flags = VFIO_IRQ_INFO_EVENTFD;
if (irq_get_trigger_type(hwirq) & IRQ_TYPE_LEVEL_MASK)
vdev->irqs[i].flags |= VFIO_IRQ_INFO_MASKABLE
| VFIO_IRQ_INFO_AUTOMASKED;
vdev->irqs[i].count = 1;
vdev->irqs[i].hwirq = hwirq;
vdev->irqs[i].masked = false;
}
vdev->num_irqs = cnt;
return 0;
err:
kfree(vdev->irqs);
return -EINVAL;
}
void vfio_platform_irq_cleanup(struct vfio_platform_device *vdev)
{
int i;
for (i = 0; i < vdev->num_irqs; i++)
vfio_set_trigger(vdev, i, -1, NULL);
vdev->num_irqs = 0;
kfree(vdev->irqs);
}