1
2
3
4
5
6
7
8#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10#include <linux/list.h>
11#include <linux/slab.h>
12#include <linux/pci.h>
13#include <linux/mutex.h>
14#include "pciback.h"
15
16#define PCI_SLOT_MAX 32
17
18struct vpci_dev_data {
19
20 struct list_head dev_list[PCI_SLOT_MAX];
21 struct mutex lock;
22};
23
24static inline struct list_head *list_first(struct list_head *head)
25{
26 return head->next;
27}
28
29static struct pci_dev *__xen_pcibk_get_pci_dev(struct xen_pcibk_device *pdev,
30 unsigned int domain,
31 unsigned int bus,
32 unsigned int devfn)
33{
34 struct pci_dev_entry *entry;
35 struct pci_dev *dev = NULL;
36 struct vpci_dev_data *vpci_dev = pdev->pci_dev_data;
37
38 if (domain != 0 || bus != 0)
39 return NULL;
40
41 if (PCI_SLOT(devfn) < PCI_SLOT_MAX) {
42 mutex_lock(&vpci_dev->lock);
43
44 list_for_each_entry(entry,
45 &vpci_dev->dev_list[PCI_SLOT(devfn)],
46 list) {
47 if (PCI_FUNC(entry->dev->devfn) == PCI_FUNC(devfn)) {
48 dev = entry->dev;
49 break;
50 }
51 }
52
53 mutex_unlock(&vpci_dev->lock);
54 }
55 return dev;
56}
57
58static inline int match_slot(struct pci_dev *l, struct pci_dev *r)
59{
60 if (pci_domain_nr(l->bus) == pci_domain_nr(r->bus)
61 && l->bus == r->bus && PCI_SLOT(l->devfn) == PCI_SLOT(r->devfn))
62 return 1;
63
64 return 0;
65}
66
67static int __xen_pcibk_add_pci_dev(struct xen_pcibk_device *pdev,
68 struct pci_dev *dev, int devid,
69 publish_pci_dev_cb publish_cb)
70{
71 int err = 0, slot, func = -1;
72 struct pci_dev_entry *t, *dev_entry;
73 struct vpci_dev_data *vpci_dev = pdev->pci_dev_data;
74
75 if ((dev->class >> 24) == PCI_BASE_CLASS_BRIDGE) {
76 err = -EFAULT;
77 xenbus_dev_fatal(pdev->xdev, err,
78 "Can't export bridges on the virtual PCI bus");
79 goto out;
80 }
81
82 dev_entry = kmalloc(sizeof(*dev_entry), GFP_KERNEL);
83 if (!dev_entry) {
84 err = -ENOMEM;
85 xenbus_dev_fatal(pdev->xdev, err,
86 "Error adding entry to virtual PCI bus");
87 goto out;
88 }
89
90 dev_entry->dev = dev;
91
92 mutex_lock(&vpci_dev->lock);
93
94
95
96
97
98 if (!dev->is_virtfn) {
99 for (slot = 0; slot < PCI_SLOT_MAX; slot++) {
100 if (list_empty(&vpci_dev->dev_list[slot]))
101 continue;
102
103 t = list_entry(list_first(&vpci_dev->dev_list[slot]),
104 struct pci_dev_entry, list);
105
106 if (match_slot(dev, t->dev)) {
107 pr_info("vpci: %s: assign to virtual slot %d func %d\n",
108 pci_name(dev), slot,
109 PCI_FUNC(dev->devfn));
110 list_add_tail(&dev_entry->list,
111 &vpci_dev->dev_list[slot]);
112 func = PCI_FUNC(dev->devfn);
113 goto unlock;
114 }
115 }
116 }
117
118
119 for (slot = 0; slot < PCI_SLOT_MAX; slot++) {
120 if (list_empty(&vpci_dev->dev_list[slot])) {
121 pr_info("vpci: %s: assign to virtual slot %d\n",
122 pci_name(dev), slot);
123 list_add_tail(&dev_entry->list,
124 &vpci_dev->dev_list[slot]);
125 func = dev->is_virtfn ? 0 : PCI_FUNC(dev->devfn);
126 goto unlock;
127 }
128 }
129
130 err = -ENOMEM;
131 xenbus_dev_fatal(pdev->xdev, err,
132 "No more space on root virtual PCI bus");
133
134unlock:
135 mutex_unlock(&vpci_dev->lock);
136
137
138 if (!err)
139 err = publish_cb(pdev, 0, 0, PCI_DEVFN(slot, func), devid);
140
141out:
142 return err;
143}
144
145static void __xen_pcibk_release_pci_dev(struct xen_pcibk_device *pdev,
146 struct pci_dev *dev)
147{
148 int slot;
149 struct vpci_dev_data *vpci_dev = pdev->pci_dev_data;
150 struct pci_dev *found_dev = NULL;
151
152 mutex_lock(&vpci_dev->lock);
153
154 for (slot = 0; slot < PCI_SLOT_MAX; slot++) {
155 struct pci_dev_entry *e;
156
157 list_for_each_entry(e, &vpci_dev->dev_list[slot], list) {
158 if (e->dev == dev) {
159 list_del(&e->list);
160 found_dev = e->dev;
161 kfree(e);
162 goto out;
163 }
164 }
165 }
166
167out:
168 mutex_unlock(&vpci_dev->lock);
169
170 if (found_dev)
171 pcistub_put_pci_dev(found_dev);
172}
173
174static int __xen_pcibk_init_devices(struct xen_pcibk_device *pdev)
175{
176 int slot;
177 struct vpci_dev_data *vpci_dev;
178
179 vpci_dev = kmalloc(sizeof(*vpci_dev), GFP_KERNEL);
180 if (!vpci_dev)
181 return -ENOMEM;
182
183 mutex_init(&vpci_dev->lock);
184
185 for (slot = 0; slot < PCI_SLOT_MAX; slot++)
186 INIT_LIST_HEAD(&vpci_dev->dev_list[slot]);
187
188 pdev->pci_dev_data = vpci_dev;
189
190 return 0;
191}
192
193static int __xen_pcibk_publish_pci_roots(struct xen_pcibk_device *pdev,
194 publish_pci_root_cb publish_cb)
195{
196
197 return publish_cb(pdev, 0, 0);
198}
199
200static void __xen_pcibk_release_devices(struct xen_pcibk_device *pdev)
201{
202 int slot;
203 struct vpci_dev_data *vpci_dev = pdev->pci_dev_data;
204
205 for (slot = 0; slot < PCI_SLOT_MAX; slot++) {
206 struct pci_dev_entry *e, *tmp;
207 list_for_each_entry_safe(e, tmp, &vpci_dev->dev_list[slot],
208 list) {
209 list_del(&e->list);
210 pcistub_put_pci_dev(e->dev);
211 kfree(e);
212 }
213 }
214
215 kfree(vpci_dev);
216 pdev->pci_dev_data = NULL;
217}
218
219static int __xen_pcibk_get_pcifront_dev(struct pci_dev *pcidev,
220 struct xen_pcibk_device *pdev,
221 unsigned int *domain, unsigned int *bus,
222 unsigned int *devfn)
223{
224 struct pci_dev_entry *entry;
225 struct pci_dev *dev = NULL;
226 struct vpci_dev_data *vpci_dev = pdev->pci_dev_data;
227 int found = 0, slot;
228
229 mutex_lock(&vpci_dev->lock);
230 for (slot = 0; slot < PCI_SLOT_MAX; slot++) {
231 list_for_each_entry(entry,
232 &vpci_dev->dev_list[slot],
233 list) {
234 dev = entry->dev;
235 if (dev && dev->bus->number == pcidev->bus->number
236 && pci_domain_nr(dev->bus) ==
237 pci_domain_nr(pcidev->bus)
238 && dev->devfn == pcidev->devfn) {
239 found = 1;
240 *domain = 0;
241 *bus = 0;
242 *devfn = PCI_DEVFN(slot,
243 PCI_FUNC(pcidev->devfn));
244 }
245 }
246 }
247 mutex_unlock(&vpci_dev->lock);
248 return found;
249}
250
251const struct xen_pcibk_backend xen_pcibk_vpci_backend = {
252 .name = "vpci",
253 .init = __xen_pcibk_init_devices,
254 .free = __xen_pcibk_release_devices,
255 .find = __xen_pcibk_get_pcifront_dev,
256 .publish = __xen_pcibk_publish_pci_roots,
257 .release = __xen_pcibk_release_pci_dev,
258 .add = __xen_pcibk_add_pci_dev,
259 .get = __xen_pcibk_get_pci_dev,
260};
261
