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
vfio_fsl_mc_irqs_allocate(struct vfio_fsl_mc_device * vdev)16 static 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
vfio_fsl_mc_irq_handler(int irq_num,void * arg)54 static 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
vfio_set_trigger(struct vfio_fsl_mc_device * vdev,int index,int fd)62 static 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]->msi_desc->irq;
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
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)106 static 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->reflck->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->reflck->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]->msi_desc->irq;
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
156 unlock:
157 mutex_unlock(&vdev->reflck->lock);
158 return ret;
159
160 }
161
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)162 int 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 */
vfio_fsl_mc_irqs_cleanup(struct vfio_fsl_mc_device * vdev)175 void 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 }
195