1// SPDX-License-Identifier: GPL-2.0
2/* Copyright(c) 2023 Advanced Micro Devices, Inc. */
3
4#include <linux/vfio.h>
5#include <linux/vfio_pci_core.h>
6
7#include "lm.h"
8#include "dirty.h"
9#include "vfio_dev.h"
10
11struct pci_dev *pds_vfio_to_pci_dev(struct pds_vfio_pci_device *pds_vfio)
12{
13	return pds_vfio->vfio_coredev.pdev;
14}
15
16struct device *pds_vfio_to_dev(struct pds_vfio_pci_device *pds_vfio)
17{
18	return &pds_vfio_to_pci_dev(pds_vfio)->dev;
19}
20
21struct pds_vfio_pci_device *pds_vfio_pci_drvdata(struct pci_dev *pdev)
22{
23	struct vfio_pci_core_device *core_device = dev_get_drvdata(&pdev->dev);
24
25	return container_of(core_device, struct pds_vfio_pci_device,
26			    vfio_coredev);
27}
28
29void pds_vfio_state_mutex_unlock(struct pds_vfio_pci_device *pds_vfio)
30{
31again:
32	mutex_lock(&pds_vfio->reset_mutex);
33	if (pds_vfio->deferred_reset) {
34		pds_vfio->deferred_reset = false;
35		pds_vfio_put_restore_file(pds_vfio);
36		pds_vfio_put_save_file(pds_vfio);
37		if (pds_vfio->state == VFIO_DEVICE_STATE_ERROR) {
38			pds_vfio_dirty_disable(pds_vfio, false);
39		}
40		pds_vfio->state = pds_vfio->deferred_reset_state;
41		pds_vfio->deferred_reset_state = VFIO_DEVICE_STATE_RUNNING;
42		mutex_unlock(&pds_vfio->reset_mutex);
43		goto again;
44	}
45	mutex_unlock(&pds_vfio->state_mutex);
46	mutex_unlock(&pds_vfio->reset_mutex);
47}
48
49void pds_vfio_reset(struct pds_vfio_pci_device *pds_vfio)
50{
51	mutex_lock(&pds_vfio->reset_mutex);
52	pds_vfio->deferred_reset = true;
53	pds_vfio->deferred_reset_state = VFIO_DEVICE_STATE_RUNNING;
54	if (!mutex_trylock(&pds_vfio->state_mutex)) {
55		mutex_unlock(&pds_vfio->reset_mutex);
56		return;
57	}
58	mutex_unlock(&pds_vfio->reset_mutex);
59	pds_vfio_state_mutex_unlock(pds_vfio);
60}
61
62static struct file *
63pds_vfio_set_device_state(struct vfio_device *vdev,
64			  enum vfio_device_mig_state new_state)
65{
66	struct pds_vfio_pci_device *pds_vfio =
67		container_of(vdev, struct pds_vfio_pci_device,
68			     vfio_coredev.vdev);
69	struct file *res = NULL;
70
71	mutex_lock(&pds_vfio->state_mutex);
72	/*
73	 * only way to transition out of VFIO_DEVICE_STATE_ERROR is via
74	 * VFIO_DEVICE_RESET, so prevent the state machine from running since
75	 * vfio_mig_get_next_state() will throw a WARN_ON() when transitioning
76	 * from VFIO_DEVICE_STATE_ERROR to any other state
77	 */
78	while (pds_vfio->state != VFIO_DEVICE_STATE_ERROR &&
79	       new_state != pds_vfio->state) {
80		enum vfio_device_mig_state next_state;
81
82		int err = vfio_mig_get_next_state(vdev, pds_vfio->state,
83						  new_state, &next_state);
84		if (err) {
85			res = ERR_PTR(err);
86			break;
87		}
88
89		res = pds_vfio_step_device_state_locked(pds_vfio, next_state);
90		if (IS_ERR(res))
91			break;
92
93		pds_vfio->state = next_state;
94
95		if (WARN_ON(res && new_state != pds_vfio->state)) {
96			res = ERR_PTR(-EINVAL);
97			break;
98		}
99	}
100	pds_vfio_state_mutex_unlock(pds_vfio);
101	/* still waiting on a deferred_reset */
102	if (pds_vfio->state == VFIO_DEVICE_STATE_ERROR)
103		res = ERR_PTR(-EIO);
104
105	return res;
106}
107
108static int pds_vfio_get_device_state(struct vfio_device *vdev,
109				     enum vfio_device_mig_state *current_state)
110{
111	struct pds_vfio_pci_device *pds_vfio =
112		container_of(vdev, struct pds_vfio_pci_device,
113			     vfio_coredev.vdev);
114
115	mutex_lock(&pds_vfio->state_mutex);
116	*current_state = pds_vfio->state;
117	pds_vfio_state_mutex_unlock(pds_vfio);
118	return 0;
119}
120
121static int pds_vfio_get_device_state_size(struct vfio_device *vdev,
122					  unsigned long *stop_copy_length)
123{
124	*stop_copy_length = PDS_LM_DEVICE_STATE_LENGTH;
125	return 0;
126}
127
128static const struct vfio_migration_ops pds_vfio_lm_ops = {
129	.migration_set_state = pds_vfio_set_device_state,
130	.migration_get_state = pds_vfio_get_device_state,
131	.migration_get_data_size = pds_vfio_get_device_state_size
132};
133
134static const struct vfio_log_ops pds_vfio_log_ops = {
135	.log_start = pds_vfio_dma_logging_start,
136	.log_stop = pds_vfio_dma_logging_stop,
137	.log_read_and_clear = pds_vfio_dma_logging_report,
138};
139
140static int pds_vfio_init_device(struct vfio_device *vdev)
141{
142	struct pds_vfio_pci_device *pds_vfio =
143		container_of(vdev, struct pds_vfio_pci_device,
144			     vfio_coredev.vdev);
145	struct pci_dev *pdev = to_pci_dev(vdev->dev);
146	int err, vf_id, pci_id;
147
148	vf_id = pci_iov_vf_id(pdev);
149	if (vf_id < 0)
150		return vf_id;
151
152	err = vfio_pci_core_init_dev(vdev);
153	if (err)
154		return err;
155
156	pds_vfio->vf_id = vf_id;
157
158	mutex_init(&pds_vfio->state_mutex);
159	mutex_init(&pds_vfio->reset_mutex);
160
161	vdev->migration_flags = VFIO_MIGRATION_STOP_COPY | VFIO_MIGRATION_P2P;
162	vdev->mig_ops = &pds_vfio_lm_ops;
163	vdev->log_ops = &pds_vfio_log_ops;
164
165	pci_id = PCI_DEVID(pdev->bus->number, pdev->devfn);
166	dev_dbg(&pdev->dev,
167		"%s: PF %#04x VF %#04x vf_id %d domain %d pds_vfio %p\n",
168		__func__, pci_dev_id(pci_physfn(pdev)), pci_id, vf_id,
169		pci_domain_nr(pdev->bus), pds_vfio);
170
171	return 0;
172}
173
174static void pds_vfio_release_device(struct vfio_device *vdev)
175{
176	struct pds_vfio_pci_device *pds_vfio =
177		container_of(vdev, struct pds_vfio_pci_device,
178			     vfio_coredev.vdev);
179
180	mutex_destroy(&pds_vfio->state_mutex);
181	mutex_destroy(&pds_vfio->reset_mutex);
182	vfio_pci_core_release_dev(vdev);
183}
184
185static int pds_vfio_open_device(struct vfio_device *vdev)
186{
187	struct pds_vfio_pci_device *pds_vfio =
188		container_of(vdev, struct pds_vfio_pci_device,
189			     vfio_coredev.vdev);
190	int err;
191
192	err = vfio_pci_core_enable(&pds_vfio->vfio_coredev);
193	if (err)
194		return err;
195
196	pds_vfio->state = VFIO_DEVICE_STATE_RUNNING;
197	pds_vfio->deferred_reset_state = VFIO_DEVICE_STATE_RUNNING;
198
199	vfio_pci_core_finish_enable(&pds_vfio->vfio_coredev);
200
201	return 0;
202}
203
204static void pds_vfio_close_device(struct vfio_device *vdev)
205{
206	struct pds_vfio_pci_device *pds_vfio =
207		container_of(vdev, struct pds_vfio_pci_device,
208			     vfio_coredev.vdev);
209
210	mutex_lock(&pds_vfio->state_mutex);
211	pds_vfio_put_restore_file(pds_vfio);
212	pds_vfio_put_save_file(pds_vfio);
213	pds_vfio_dirty_disable(pds_vfio, true);
214	mutex_unlock(&pds_vfio->state_mutex);
215	vfio_pci_core_close_device(vdev);
216}
217
218static const struct vfio_device_ops pds_vfio_ops = {
219	.name = "pds-vfio",
220	.init = pds_vfio_init_device,
221	.release = pds_vfio_release_device,
222	.open_device = pds_vfio_open_device,
223	.close_device = pds_vfio_close_device,
224	.ioctl = vfio_pci_core_ioctl,
225	.device_feature = vfio_pci_core_ioctl_feature,
226	.read = vfio_pci_core_read,
227	.write = vfio_pci_core_write,
228	.mmap = vfio_pci_core_mmap,
229	.request = vfio_pci_core_request,
230	.match = vfio_pci_core_match,
231	.bind_iommufd = vfio_iommufd_physical_bind,
232	.unbind_iommufd = vfio_iommufd_physical_unbind,
233	.attach_ioas = vfio_iommufd_physical_attach_ioas,
234};
235
236const struct vfio_device_ops *pds_vfio_ops_info(void)
237{
238	return &pds_vfio_ops;
239}
240