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1// SPDX-License-Identifier: GPL-2.02/*3 * Copyright (C) 2022-2023, Advanced Micro Devices, Inc.4 */5 6#include <linux/vfio.h>7#include <linux/slab.h>8#include <linux/types.h>9#include <linux/eventfd.h>10#include <linux/msi.h>11#include <linux/interrupt.h>12 13#include "linux/cdx/cdx_bus.h"14#include "private.h"15 16static irqreturn_t vfio_cdx_msihandler(int irq_no, void *arg)17{18 struct eventfd_ctx *trigger = arg;19 20 eventfd_signal(trigger);21 return IRQ_HANDLED;22}23 24static int vfio_cdx_msi_enable(struct vfio_cdx_device *vdev, int nvec)25{26 struct cdx_device *cdx_dev = to_cdx_device(vdev->vdev.dev);27 struct device *dev = vdev->vdev.dev;28 int msi_idx, ret;29 30 vdev->cdx_irqs = kcalloc(nvec, sizeof(struct vfio_cdx_irq), GFP_KERNEL);31 if (!vdev->cdx_irqs)32 return -ENOMEM;33 34 ret = cdx_enable_msi(cdx_dev);35 if (ret) {36 kfree(vdev->cdx_irqs);37 return ret;38 }39 40 /* Allocate cdx MSIs */41 ret = msi_domain_alloc_irqs(dev, MSI_DEFAULT_DOMAIN, nvec);42 if (ret) {43 cdx_disable_msi(cdx_dev);44 kfree(vdev->cdx_irqs);45 return ret;46 }47 48 for (msi_idx = 0; msi_idx < nvec; msi_idx++)49 vdev->cdx_irqs[msi_idx].irq_no = msi_get_virq(dev, msi_idx);50 51 vdev->msi_count = nvec;52 vdev->config_msi = 1;53 54 return 0;55}56 57static int vfio_cdx_msi_set_vector_signal(struct vfio_cdx_device *vdev,58 int vector, int fd)59{60 struct eventfd_ctx *trigger;61 int irq_no, ret;62 63 if (vector < 0 || vector >= vdev->msi_count)64 return -EINVAL;65 66 irq_no = vdev->cdx_irqs[vector].irq_no;67 68 if (vdev->cdx_irqs[vector].trigger) {69 free_irq(irq_no, vdev->cdx_irqs[vector].trigger);70 kfree(vdev->cdx_irqs[vector].name);71 eventfd_ctx_put(vdev->cdx_irqs[vector].trigger);72 vdev->cdx_irqs[vector].trigger = NULL;73 }74 75 if (fd < 0)76 return 0;77 78 vdev->cdx_irqs[vector].name = kasprintf(GFP_KERNEL, "vfio-msi[%d](%s)",79 vector, dev_name(vdev->vdev.dev));80 if (!vdev->cdx_irqs[vector].name)81 return -ENOMEM;82 83 trigger = eventfd_ctx_fdget(fd);84 if (IS_ERR(trigger)) {85 kfree(vdev->cdx_irqs[vector].name);86 return PTR_ERR(trigger);87 }88 89 ret = request_irq(irq_no, vfio_cdx_msihandler, 0,90 vdev->cdx_irqs[vector].name, trigger);91 if (ret) {92 kfree(vdev->cdx_irqs[vector].name);93 eventfd_ctx_put(trigger);94 return ret;95 }96 97 vdev->cdx_irqs[vector].trigger = trigger;98 99 return 0;100}101 102static int vfio_cdx_msi_set_block(struct vfio_cdx_device *vdev,103 unsigned int start, unsigned int count,104 int32_t *fds)105{106 int i, j, ret = 0;107 108 if (start >= vdev->msi_count || start + count > vdev->msi_count)109 return -EINVAL;110 111 for (i = 0, j = start; i < count && !ret; i++, j++) {112 int fd = fds ? fds[i] : -1;113 114 ret = vfio_cdx_msi_set_vector_signal(vdev, j, fd);115 }116 117 if (ret) {118 for (--j; j >= (int)start; j--)119 vfio_cdx_msi_set_vector_signal(vdev, j, -1);120 }121 122 return ret;123}124 125static void vfio_cdx_msi_disable(struct vfio_cdx_device *vdev)126{127 struct cdx_device *cdx_dev = to_cdx_device(vdev->vdev.dev);128 struct device *dev = vdev->vdev.dev;129 130 vfio_cdx_msi_set_block(vdev, 0, vdev->msi_count, NULL);131 132 if (!vdev->config_msi)133 return;134 135 msi_domain_free_irqs_all(dev, MSI_DEFAULT_DOMAIN);136 cdx_disable_msi(cdx_dev);137 kfree(vdev->cdx_irqs);138 139 vdev->cdx_irqs = NULL;140 vdev->msi_count = 0;141 vdev->config_msi = 0;142}143 144static int vfio_cdx_set_msi_trigger(struct vfio_cdx_device *vdev,145 unsigned int index, unsigned int start,146 unsigned int count, u32 flags,147 void *data)148{149 struct cdx_device *cdx_dev = to_cdx_device(vdev->vdev.dev);150 int i;151 152 if (start + count > cdx_dev->num_msi)153 return -EINVAL;154 155 if (!count && (flags & VFIO_IRQ_SET_DATA_NONE)) {156 vfio_cdx_msi_disable(vdev);157 return 0;158 }159 160 if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {161 s32 *fds = data;162 int ret;163 164 if (vdev->config_msi)165 return vfio_cdx_msi_set_block(vdev, start, count,166 fds);167 ret = vfio_cdx_msi_enable(vdev, cdx_dev->num_msi);168 if (ret)169 return ret;170 171 ret = vfio_cdx_msi_set_block(vdev, start, count, fds);172 if (ret)173 vfio_cdx_msi_disable(vdev);174 175 return ret;176 }177 178 for (i = start; i < start + count; i++) {179 if (!vdev->cdx_irqs[i].trigger)180 continue;181 if (flags & VFIO_IRQ_SET_DATA_NONE) {182 eventfd_signal(vdev->cdx_irqs[i].trigger);183 } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {184 u8 *bools = data;185 186 if (bools[i - start])187 eventfd_signal(vdev->cdx_irqs[i].trigger);188 }189 }190 191 return 0;192}193 194int vfio_cdx_set_irqs_ioctl(struct vfio_cdx_device *vdev,195 u32 flags, unsigned int index,196 unsigned int start, unsigned int count,197 void *data)198{199 if (flags & VFIO_IRQ_SET_ACTION_TRIGGER)200 return vfio_cdx_set_msi_trigger(vdev, index, start,201 count, flags, data);202 else203 return -EINVAL;204}205 206/* Free All IRQs for the given device */207void vfio_cdx_irqs_cleanup(struct vfio_cdx_device *vdev)208{209 /*210 * Device does not support any interrupt or the interrupts211 * were not configured212 */213 if (!vdev->cdx_irqs)214 return;215 216 vfio_cdx_set_msi_trigger(vdev, 0, 0, 0, VFIO_IRQ_SET_DATA_NONE, NULL);217}218