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
vfio_fsl_mc_irqs_allocate(struct vfio_fsl_mc_device * vdev)15 static 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(irq_count, 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(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
vfio_fsl_mc_irq_handler(int irq_num,void * arg)53 static 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(mc_irq->trigger);
58 return IRQ_HANDLED;
59 }
60
vfio_set_trigger(struct vfio_fsl_mc_device * vdev,int index,int fd)61 static 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(irq->name);
73 eventfd_ctx_put(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, "vfio-irq[%d](%s)",
81 hwirq, dev_name(&vdev->mc_dev->dev));
82 if (!irq->name)
83 return -ENOMEM;
84
85 trigger = eventfd_ctx_fdget(fd);
86 if (IS_ERR(trigger)) {
87 kfree(irq->name);
88 return PTR_ERR(trigger);
89 }
90
91 irq->trigger = trigger;
92
93 ret = request_irq(hwirq, vfio_fsl_mc_irq_handler, 0,
94 irq->name, irq);
95 if (ret) {
96 kfree(irq->name);
97 eventfd_ctx_put(trigger);
98 irq->trigger = NULL;
99 return ret;
100 }
101
102 return 0;
103 }
104
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)105 static 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 struct vfio_fsl_mc_irq *irq;
112 struct device *cont_dev = fsl_mc_cont_dev(&mc_dev->dev);
113 struct fsl_mc_device *mc_cont = to_fsl_mc_device(cont_dev);
114 int ret;
115
116 if (!count && (flags & VFIO_IRQ_SET_DATA_NONE))
117 return vfio_set_trigger(vdev, index, -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_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(&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 irq = &vdev->mc_irqs[index];
140
141 if (flags & VFIO_IRQ_SET_DATA_NONE) {
142 if (irq->trigger)
143 eventfd_signal(irq->trigger);
144
145 } else if (flags & VFIO_IRQ_SET_DATA_BOOL) {
146 u8 trigger = *(u8 *)data;
147
148 if (trigger && irq->trigger)
149 eventfd_signal(irq->trigger);
150 }
151
152 return 0;
153
154 unlock:
155 mutex_unlock(&vdev->vdev.dev_set->lock);
156 return ret;
157
158 }
159
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)160 int vfio_fsl_mc_set_irqs_ioctl(struct vfio_fsl_mc_device *vdev,
161 u32 flags, unsigned int index,
162 unsigned int start, unsigned int count,
163 void *data)
164 {
165 if (flags & VFIO_IRQ_SET_ACTION_TRIGGER)
166 return vfio_fsl_mc_set_irq_trigger(vdev, index, start,
167 count, flags, data);
168 else
169 return -EINVAL;
170 }
171
172 /* Free All IRQs for the given MC object */
vfio_fsl_mc_irqs_cleanup(struct vfio_fsl_mc_device * vdev)173 void vfio_fsl_mc_irqs_cleanup(struct vfio_fsl_mc_device *vdev)
174 {
175 struct fsl_mc_device *mc_dev = vdev->mc_dev;
176 int irq_count = mc_dev->obj_desc.irq_count;
177 int i;
178
179 /*
180 * Device does not support any interrupt or the interrupts
181 * were not configured
182 */
183 if (!vdev->mc_irqs)
184 return;
185
186 for (i = 0; i < irq_count; i++)
187 vfio_set_trigger(vdev, i, -1);
188
189 fsl_mc_free_irqs(mc_dev);
190 kfree(vdev->mc_irqs);
191 vdev->mc_irqs = NULL;
192 }
193