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
12#include "linux/fsl/mc.h"
13#include "vfio_fsl_mc_private.h"
14
15static int vfio_fsl_mc_irqs_allocate(struct vfio_fsl_mc_device *vdev)
16{
17 struct fsl_mc_device *mc_dev = vdev->mc_dev;
18 struct vfio_fsl_mc_irq *mc_irq;
19 int irq_count;
20 int ret, i;
21
22 /* Device does not support any interrupt */
23 if (mc_dev->obj_desc.irq_count == 0)
24 return 0;
25
26 /* interrupts were already allocated for this device */
27 if (vdev->mc_irqs)
28 return 0;
29
30 irq_count = mc_dev->obj_desc.irq_count;
31
32 mc_irq = kcalloc(n: irq_count, size: sizeof(*mc_irq), GFP_KERNEL_ACCOUNT);
33 if (!mc_irq)
34 return -ENOMEM;
35
36 /* Allocate IRQs */
37 ret = fsl_mc_allocate_irqs(mc_dev);
38 if (ret) {
39 kfree(objp: mc_irq);
40 return ret;
41 }
42
43 for (i = 0; i < irq_count; i++) {
44 mc_irq[i].count = 1;
45 mc_irq[i].flags = VFIO_IRQ_INFO_EVENTFD;
46 }
47
48 vdev->mc_irqs = mc_irq;
49
50 return 0;
51}
52
53static irqreturn_t vfio_fsl_mc_irq_handler(int irq_num, void *arg)
54{
55 struct vfio_fsl_mc_irq *mc_irq = (struct vfio_fsl_mc_irq *)arg;
56
57 eventfd_signal(ctx: mc_irq->trigger);
58 return IRQ_HANDLED;
59}
60
61static int vfio_set_trigger(struct vfio_fsl_mc_device *vdev,
62 int index, int fd)
63{
64 struct vfio_fsl_mc_irq *irq = &vdev->mc_irqs[index];
65 struct eventfd_ctx *trigger;
66 int hwirq;
67 int ret;
68
69 hwirq = vdev->mc_dev->irqs[index]->virq;
70 if (irq->trigger) {
71 free_irq(hwirq, irq);
72 kfree(objp: irq->name);
73 eventfd_ctx_put(ctx: irq->trigger);
74 irq->trigger = NULL;
75 }
76
77 if (fd < 0) /* Disable only */
78 return 0;
79
80 irq->name = kasprintf(GFP_KERNEL_ACCOUNT, fmt: "vfio-irq[%d](%s)",
81 hwirq, dev_name(dev: &vdev->mc_dev->dev));
82 if (!irq->name)
83 return -ENOMEM;
84
85 trigger = eventfd_ctx_fdget(fd);
86 if (IS_ERR(ptr: trigger)) {
87 kfree(objp: irq->name);
88 return PTR_ERR(ptr: trigger);
89 }
90
91 irq->trigger = trigger;
92
93 ret = request_irq(irq: hwirq, handler: vfio_fsl_mc_irq_handler, flags: 0,
94 name: irq->name, dev: irq);
95 if (ret) {
96 kfree(objp: irq->name);
97 eventfd_ctx_put(ctx: trigger);
98 irq->trigger = NULL;
99 return ret;
100 }
101
102 return 0;
103}
104
105static int vfio_fsl_mc_set_irq_trigger(struct vfio_fsl_mc_device *vdev,
106 unsigned int index, unsigned int start,
107 unsigned int count, u32 flags,
108 void *data)
109{
110 struct fsl_mc_device *mc_dev = vdev->mc_dev;
111 int ret, hwirq;
112 struct vfio_fsl_mc_irq *irq;
113 struct device *cont_dev = fsl_mc_cont_dev(&mc_dev->dev);
114 struct fsl_mc_device *mc_cont = to_fsl_mc_device(cont_dev);
115
116 if (!count && (flags & VFIO_IRQ_SET_DATA_NONE))
117 return vfio_set_trigger(vdev, index, fd: -1);
118
119 if (start != 0 || count != 1)
120 return -EINVAL;
121
122 mutex_lock(&vdev->vdev.dev_set->lock);
123 ret = fsl_mc_populate_irq_pool(mc_bus_dev: mc_cont,
124 FSL_MC_IRQ_POOL_MAX_TOTAL_IRQS);
125 if (ret)
126 goto unlock;
127
128 ret = vfio_fsl_mc_irqs_allocate(vdev);
129 if (ret)
130 goto unlock;
131 mutex_unlock(lock: &vdev->vdev.dev_set->lock);
132
133 if (flags & VFIO_IRQ_SET_DATA_EVENTFD) {
134 s32 fd = *(s32 *)data;
135
136 return vfio_set_trigger(vdev, index, fd);
137 }
138
139 hwirq = vdev->mc_dev->irqs[index]->virq;
140
141 irq = &vdev->mc_irqs[index];
142
143 if (flags & VFIO_IRQ_SET_DATA_NONE) {
144 if (irq->trigger)
145 eventfd_signal(ctx: irq->trigger);
146
147 } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
148 u8 trigger = *(u8 *)data;
149
150 if (trigger && irq->trigger)
151 eventfd_signal(ctx: irq->trigger);
152 }
153
154 return 0;
155
156unlock:
157 mutex_unlock(lock: &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, index: i, fd: -1);
190
191 fsl_mc_free_irqs(mc_dev);
192 kfree(objp: vdev->mc_irqs);
193 vdev->mc_irqs = NULL;
194}
195

source code of linux/drivers/vfio/fsl-mc/vfio_fsl_mc_intr.c