Commit | Line | Data |
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30edc14b KRW |
1 | /* |
2 | * PCI Backend - Provides a Virtual PCI bus (with real devices) | |
3 | * to the frontend | |
4 | * | |
5 | * Author: Ryan Wilson <hap9@epoch.ncsc.mil> | |
6 | */ | |
7 | ||
8 | #include <linux/list.h> | |
9 | #include <linux/slab.h> | |
10 | #include <linux/pci.h> | |
74d33ded | 11 | #include <linux/mutex.h> |
30edc14b KRW |
12 | #include "pciback.h" |
13 | ||
14 | #define PCI_SLOT_MAX 32 | |
15 | ||
16 | struct vpci_dev_data { | |
17 | /* Access to dev_list must be protected by lock */ | |
18 | struct list_head dev_list[PCI_SLOT_MAX]; | |
74d33ded | 19 | struct mutex lock; |
30edc14b KRW |
20 | }; |
21 | ||
22 | static inline struct list_head *list_first(struct list_head *head) | |
23 | { | |
24 | return head->next; | |
25 | } | |
26 | ||
2ebdc426 KRW |
27 | static struct pci_dev *__xen_pcibk_get_pci_dev(struct xen_pcibk_device *pdev, |
28 | unsigned int domain, | |
29 | unsigned int bus, | |
30 | unsigned int devfn) | |
30edc14b KRW |
31 | { |
32 | struct pci_dev_entry *entry; | |
33 | struct pci_dev *dev = NULL; | |
34 | struct vpci_dev_data *vpci_dev = pdev->pci_dev_data; | |
30edc14b KRW |
35 | |
36 | if (domain != 0 || bus != 0) | |
37 | return NULL; | |
38 | ||
39 | if (PCI_SLOT(devfn) < PCI_SLOT_MAX) { | |
74d33ded | 40 | mutex_lock(&vpci_dev->lock); |
30edc14b KRW |
41 | |
42 | list_for_each_entry(entry, | |
43 | &vpci_dev->dev_list[PCI_SLOT(devfn)], | |
44 | list) { | |
45 | if (PCI_FUNC(entry->dev->devfn) == PCI_FUNC(devfn)) { | |
46 | dev = entry->dev; | |
47 | break; | |
48 | } | |
49 | } | |
50 | ||
74d33ded | 51 | mutex_unlock(&vpci_dev->lock); |
30edc14b KRW |
52 | } |
53 | return dev; | |
54 | } | |
55 | ||
56 | static inline int match_slot(struct pci_dev *l, struct pci_dev *r) | |
57 | { | |
58 | if (pci_domain_nr(l->bus) == pci_domain_nr(r->bus) | |
59 | && l->bus == r->bus && PCI_SLOT(l->devfn) == PCI_SLOT(r->devfn)) | |
60 | return 1; | |
61 | ||
62 | return 0; | |
63 | } | |
64 | ||
2ebdc426 KRW |
65 | static int __xen_pcibk_add_pci_dev(struct xen_pcibk_device *pdev, |
66 | struct pci_dev *dev, int devid, | |
67 | publish_pci_dev_cb publish_cb) | |
30edc14b KRW |
68 | { |
69 | int err = 0, slot, func = -1; | |
70 | struct pci_dev_entry *t, *dev_entry; | |
71 | struct vpci_dev_data *vpci_dev = pdev->pci_dev_data; | |
30edc14b KRW |
72 | |
73 | if ((dev->class >> 24) == PCI_BASE_CLASS_BRIDGE) { | |
74 | err = -EFAULT; | |
75 | xenbus_dev_fatal(pdev->xdev, err, | |
76 | "Can't export bridges on the virtual PCI bus"); | |
77 | goto out; | |
78 | } | |
79 | ||
80 | dev_entry = kmalloc(sizeof(*dev_entry), GFP_KERNEL); | |
81 | if (!dev_entry) { | |
82 | err = -ENOMEM; | |
83 | xenbus_dev_fatal(pdev->xdev, err, | |
84 | "Error adding entry to virtual PCI bus"); | |
85 | goto out; | |
86 | } | |
87 | ||
88 | dev_entry->dev = dev; | |
89 | ||
74d33ded | 90 | mutex_lock(&vpci_dev->lock); |
30edc14b | 91 | |
8a5248fe LE |
92 | /* |
93 | * Keep multi-function devices together on the virtual PCI bus, except | |
94 | * virtual functions. | |
95 | */ | |
96 | if (!dev->is_virtfn) { | |
97 | for (slot = 0; slot < PCI_SLOT_MAX; slot++) { | |
98 | if (list_empty(&vpci_dev->dev_list[slot])) | |
99 | continue; | |
100 | ||
30edc14b KRW |
101 | t = list_entry(list_first(&vpci_dev->dev_list[slot]), |
102 | struct pci_dev_entry, list); | |
103 | ||
104 | if (match_slot(dev, t->dev)) { | |
a92336a1 | 105 | pr_info(DRV_NAME ": vpci: %s: " |
30edc14b KRW |
106 | "assign to virtual slot %d func %d\n", |
107 | pci_name(dev), slot, | |
108 | PCI_FUNC(dev->devfn)); | |
109 | list_add_tail(&dev_entry->list, | |
110 | &vpci_dev->dev_list[slot]); | |
111 | func = PCI_FUNC(dev->devfn); | |
112 | goto unlock; | |
113 | } | |
114 | } | |
115 | } | |
116 | ||
117 | /* Assign to a new slot on the virtual PCI bus */ | |
118 | for (slot = 0; slot < PCI_SLOT_MAX; slot++) { | |
119 | if (list_empty(&vpci_dev->dev_list[slot])) { | |
a92336a1 KRW |
120 | printk(KERN_INFO DRV_NAME |
121 | ": vpci: %s: assign to virtual slot %d\n", | |
30edc14b KRW |
122 | pci_name(dev), slot); |
123 | list_add_tail(&dev_entry->list, | |
124 | &vpci_dev->dev_list[slot]); | |
8a5248fe | 125 | func = dev->is_virtfn ? 0 : PCI_FUNC(dev->devfn); |
30edc14b KRW |
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 | ||
134 | unlock: | |
74d33ded | 135 | mutex_unlock(&vpci_dev->lock); |
30edc14b KRW |
136 | |
137 | /* Publish this device. */ | |
138 | if (!err) | |
139 | err = publish_cb(pdev, 0, 0, PCI_DEVFN(slot, func), devid); | |
140 | ||
141 | out: | |
142 | return err; | |
143 | } | |
144 | ||
2ebdc426 KRW |
145 | static void __xen_pcibk_release_pci_dev(struct xen_pcibk_device *pdev, |
146 | struct pci_dev *dev) | |
30edc14b KRW |
147 | { |
148 | int slot; | |
149 | struct vpci_dev_data *vpci_dev = pdev->pci_dev_data; | |
150 | struct pci_dev *found_dev = NULL; | |
30edc14b | 151 | |
74d33ded | 152 | mutex_lock(&vpci_dev->lock); |
30edc14b KRW |
153 | |
154 | for (slot = 0; slot < PCI_SLOT_MAX; slot++) { | |
402c5e15 JB |
155 | struct pci_dev_entry *e; |
156 | ||
157 | list_for_each_entry(e, &vpci_dev->dev_list[slot], list) { | |
30edc14b KRW |
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 | ||
167 | out: | |
74d33ded | 168 | mutex_unlock(&vpci_dev->lock); |
30edc14b KRW |
169 | |
170 | if (found_dev) | |
171 | pcistub_put_pci_dev(found_dev); | |
172 | } | |
173 | ||
2ebdc426 | 174 | static int __xen_pcibk_init_devices(struct xen_pcibk_device *pdev) |
30edc14b KRW |
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 | ||
74d33ded | 183 | mutex_init(&vpci_dev->lock); |
30edc14b KRW |
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 | ||
2ebdc426 KRW |
193 | static int __xen_pcibk_publish_pci_roots(struct xen_pcibk_device *pdev, |
194 | publish_pci_root_cb publish_cb) | |
30edc14b KRW |
195 | { |
196 | /* The Virtual PCI bus has only one root */ | |
197 | return publish_cb(pdev, 0, 0); | |
198 | } | |
199 | ||
2ebdc426 | 200 | static void __xen_pcibk_release_devices(struct xen_pcibk_device *pdev) |
30edc14b KRW |
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 | ||
2ebdc426 KRW |
219 | static 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) | |
30edc14b KRW |
223 | { |
224 | struct pci_dev_entry *entry; | |
225 | struct pci_dev *dev = NULL; | |
226 | struct vpci_dev_data *vpci_dev = pdev->pci_dev_data; | |
30edc14b KRW |
227 | int found = 0, slot; |
228 | ||
74d33ded | 229 | mutex_lock(&vpci_dev->lock); |
30edc14b KRW |
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 | } | |
e1db4cef | 247 | mutex_unlock(&vpci_dev->lock); |
30edc14b KRW |
248 | return found; |
249 | } | |
2ebdc426 | 250 | |
402c5e15 | 251 | const struct xen_pcibk_backend xen_pcibk_vpci_backend = { |
2ebdc426 KRW |
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 | }; |