cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

vfio_fsl_mc_intr.c (4227B)


      1// SPDX-License-Identifier: (GPL-2.0+ OR BSD-3-Clause)
      2/*
      3 * Copyright 2013-2016 Freescale Semiconductor Inc.
      4 * Copyright 2019 NXP
      5 */
      6
      7#include <linux/vfio.h>
      8#include <linux/slab.h>
      9#include <linux/types.h>
     10#include <linux/eventfd.h>
     11#include <linux/msi.h>
     12
     13#include "linux/fsl/mc.h"
     14#include "vfio_fsl_mc_private.h"
     15
     16static int vfio_fsl_mc_irqs_allocate(struct vfio_fsl_mc_device *vdev)
     17{
     18	struct fsl_mc_device *mc_dev = vdev->mc_dev;
     19	struct vfio_fsl_mc_irq *mc_irq;
     20	int irq_count;
     21	int ret, i;
     22
     23	/* Device does not support any interrupt */
     24	if (mc_dev->obj_desc.irq_count == 0)
     25		return 0;
     26
     27	/* interrupts were already allocated for this device */
     28	if (vdev->mc_irqs)
     29		return 0;
     30
     31	irq_count = mc_dev->obj_desc.irq_count;
     32
     33	mc_irq = kcalloc(irq_count, sizeof(*mc_irq), GFP_KERNEL);
     34	if (!mc_irq)
     35		return -ENOMEM;
     36
     37	/* Allocate IRQs */
     38	ret = fsl_mc_allocate_irqs(mc_dev);
     39	if (ret) {
     40		kfree(mc_irq);
     41		return ret;
     42	}
     43
     44	for (i = 0; i < irq_count; i++) {
     45		mc_irq[i].count = 1;
     46		mc_irq[i].flags = VFIO_IRQ_INFO_EVENTFD;
     47	}
     48
     49	vdev->mc_irqs = mc_irq;
     50
     51	return 0;
     52}
     53
     54static irqreturn_t vfio_fsl_mc_irq_handler(int irq_num, void *arg)
     55{
     56	struct vfio_fsl_mc_irq *mc_irq = (struct vfio_fsl_mc_irq *)arg;
     57
     58	eventfd_signal(mc_irq->trigger, 1);
     59	return IRQ_HANDLED;
     60}
     61
     62static int vfio_set_trigger(struct vfio_fsl_mc_device *vdev,
     63						   int index, int fd)
     64{
     65	struct vfio_fsl_mc_irq *irq = &vdev->mc_irqs[index];
     66	struct eventfd_ctx *trigger;
     67	int hwirq;
     68	int ret;
     69
     70	hwirq = vdev->mc_dev->irqs[index]->virq;
     71	if (irq->trigger) {
     72		free_irq(hwirq, irq);
     73		kfree(irq->name);
     74		eventfd_ctx_put(irq->trigger);
     75		irq->trigger = NULL;
     76	}
     77
     78	if (fd < 0) /* Disable only */
     79		return 0;
     80
     81	irq->name = kasprintf(GFP_KERNEL, "vfio-irq[%d](%s)",
     82			    hwirq, dev_name(&vdev->mc_dev->dev));
     83	if (!irq->name)
     84		return -ENOMEM;
     85
     86	trigger = eventfd_ctx_fdget(fd);
     87	if (IS_ERR(trigger)) {
     88		kfree(irq->name);
     89		return PTR_ERR(trigger);
     90	}
     91
     92	irq->trigger = trigger;
     93
     94	ret = request_irq(hwirq, vfio_fsl_mc_irq_handler, 0,
     95		  irq->name, irq);
     96	if (ret) {
     97		kfree(irq->name);
     98		eventfd_ctx_put(trigger);
     99		irq->trigger = NULL;
    100		return ret;
    101	}
    102
    103	return 0;
    104}
    105
    106static int vfio_fsl_mc_set_irq_trigger(struct vfio_fsl_mc_device *vdev,
    107				       unsigned int index, unsigned int start,
    108				       unsigned int count, u32 flags,
    109				       void *data)
    110{
    111	struct fsl_mc_device *mc_dev = vdev->mc_dev;
    112	int ret, hwirq;
    113	struct vfio_fsl_mc_irq *irq;
    114	struct device *cont_dev = fsl_mc_cont_dev(&mc_dev->dev);
    115	struct fsl_mc_device *mc_cont = to_fsl_mc_device(cont_dev);
    116
    117	if (!count && (flags & VFIO_IRQ_SET_DATA_NONE))
    118		return vfio_set_trigger(vdev, index, -1);
    119
    120	if (start != 0 || count != 1)
    121		return -EINVAL;
    122
    123	mutex_lock(&vdev->vdev.dev_set->lock);
    124	ret = fsl_mc_populate_irq_pool(mc_cont,
    125			FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
    126	if (ret)
    127		goto unlock;
    128
    129	ret = vfio_fsl_mc_irqs_allocate(vdev);
    130	if (ret)
    131		goto unlock;
    132	mutex_unlock(&vdev->vdev.dev_set->lock);
    133
    134	if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
    135		s32 fd = *(s32 *)data;
    136
    137		return vfio_set_trigger(vdev, index, fd);
    138	}
    139
    140	hwirq = vdev->mc_dev->irqs[index]->virq;
    141
    142	irq = &vdev->mc_irqs[index];
    143
    144	if (flags & VFIO_IRQ_SET_DATA_NONE) {
    145		vfio_fsl_mc_irq_handler(hwirq, irq);
    146
    147	} else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
    148		u8 trigger = *(u8 *)data;
    149
    150		if (trigger)
    151			vfio_fsl_mc_irq_handler(hwirq, irq);
    152	}
    153
    154	return 0;
    155
    156unlock:
    157	mutex_unlock(&vdev->vdev.dev_set->lock);
    158	return ret;
    159
    160}
    161
    162int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,
    163			       u32 flags, unsigned int index,
    164			       unsigned int start, unsigned int count,
    165			       void *data)
    166{
    167	if (flags & VFIO_IRQ_SET_ACTION_TRIGGER)
    168		return  vfio_fsl_mc_set_irq_trigger(vdev, index, start,
    169			  count, flags, data);
    170	else
    171		return -EINVAL;
    172}
    173
    174/* Free All IRQs for the given MC object */
    175void vfio_fsl_mc_irqs_cleanup(struct vfio_fsl_mc_device *vdev)
    176{
    177	struct fsl_mc_device *mc_dev = vdev->mc_dev;
    178	int irq_count = mc_dev->obj_desc.irq_count;
    179	int i;
    180
    181	/*
    182	 * Device does not support any interrupt or the interrupts
    183	 * were not configured
    184	 */
    185	if (!vdev->mc_irqs)
    186		return;
    187
    188	for (i = 0; i < irq_count; i++)
    189		vfio_set_trigger(vdev, i, -1);
    190
    191	fsl_mc_free_irqs(mc_dev);
    192	kfree(vdev->mc_irqs);
    193	vdev->mc_irqs = NULL;
    194}