Konrad Rzeszutek Wilk | 30edc14 | 2009-10-13 17:22:20 -0400 | [diff] [blame] | 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> |
| 11 | #include <linux/spinlock.h> |
| 12 | #include "pciback.h" |
| 13 | |
| 14 | #define PCI_SLOT_MAX 32 |
Konrad Rzeszutek Wilk | a92336a | 2011-07-19 19:40:51 -0400 | [diff] [blame] | 15 | #define DRV_NAME "xen-pciback" |
Konrad Rzeszutek Wilk | 30edc14 | 2009-10-13 17:22:20 -0400 | [diff] [blame] | 16 | |
| 17 | struct vpci_dev_data { |
| 18 | /* Access to dev_list must be protected by lock */ |
| 19 | struct list_head dev_list[PCI_SLOT_MAX]; |
| 20 | spinlock_t lock; |
| 21 | }; |
| 22 | |
| 23 | static inline struct list_head *list_first(struct list_head *head) |
| 24 | { |
| 25 | return head->next; |
| 26 | } |
| 27 | |
Konrad Rzeszutek Wilk | 2ebdc42 | 2011-07-11 16:49:41 -0400 | [diff] [blame^] | 28 | static struct pci_dev *__xen_pcibk_get_pci_dev(struct xen_pcibk_device *pdev, |
| 29 | unsigned int domain, |
| 30 | unsigned int bus, |
| 31 | unsigned int devfn) |
Konrad Rzeszutek Wilk | 30edc14 | 2009-10-13 17:22:20 -0400 | [diff] [blame] | 32 | { |
| 33 | struct pci_dev_entry *entry; |
| 34 | struct pci_dev *dev = NULL; |
| 35 | struct vpci_dev_data *vpci_dev = pdev->pci_dev_data; |
| 36 | unsigned long flags; |
| 37 | |
| 38 | if (domain != 0 || bus != 0) |
| 39 | return NULL; |
| 40 | |
| 41 | if (PCI_SLOT(devfn) < PCI_SLOT_MAX) { |
| 42 | spin_lock_irqsave(&vpci_dev->lock, flags); |
| 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 | spin_unlock_irqrestore(&vpci_dev->lock, flags); |
| 54 | } |
| 55 | return dev; |
| 56 | } |
| 57 | |
| 58 | static 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 | |
Konrad Rzeszutek Wilk | 2ebdc42 | 2011-07-11 16:49:41 -0400 | [diff] [blame^] | 67 | static 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) |
Konrad Rzeszutek Wilk | 30edc14 | 2009-10-13 17:22:20 -0400 | [diff] [blame] | 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 | unsigned long flags; |
| 75 | |
| 76 | if ((dev->class >> 24) == PCI_BASE_CLASS_BRIDGE) { |
| 77 | err = -EFAULT; |
| 78 | xenbus_dev_fatal(pdev->xdev, err, |
| 79 | "Can't export bridges on the virtual PCI bus"); |
| 80 | goto out; |
| 81 | } |
| 82 | |
| 83 | dev_entry = kmalloc(sizeof(*dev_entry), GFP_KERNEL); |
| 84 | if (!dev_entry) { |
| 85 | err = -ENOMEM; |
| 86 | xenbus_dev_fatal(pdev->xdev, err, |
| 87 | "Error adding entry to virtual PCI bus"); |
| 88 | goto out; |
| 89 | } |
| 90 | |
| 91 | dev_entry->dev = dev; |
| 92 | |
| 93 | spin_lock_irqsave(&vpci_dev->lock, flags); |
| 94 | |
| 95 | /* Keep multi-function devices together on the virtual PCI bus */ |
| 96 | for (slot = 0; slot < PCI_SLOT_MAX; slot++) { |
| 97 | if (!list_empty(&vpci_dev->dev_list[slot])) { |
| 98 | t = list_entry(list_first(&vpci_dev->dev_list[slot]), |
| 99 | struct pci_dev_entry, list); |
| 100 | |
| 101 | if (match_slot(dev, t->dev)) { |
Konrad Rzeszutek Wilk | a92336a | 2011-07-19 19:40:51 -0400 | [diff] [blame] | 102 | pr_info(DRV_NAME ": vpci: %s: " |
Konrad Rzeszutek Wilk | 30edc14 | 2009-10-13 17:22:20 -0400 | [diff] [blame] | 103 | "assign to virtual slot %d func %d\n", |
| 104 | pci_name(dev), slot, |
| 105 | PCI_FUNC(dev->devfn)); |
| 106 | list_add_tail(&dev_entry->list, |
| 107 | &vpci_dev->dev_list[slot]); |
| 108 | func = PCI_FUNC(dev->devfn); |
| 109 | goto unlock; |
| 110 | } |
| 111 | } |
| 112 | } |
| 113 | |
| 114 | /* Assign to a new slot on the virtual PCI bus */ |
| 115 | for (slot = 0; slot < PCI_SLOT_MAX; slot++) { |
| 116 | if (list_empty(&vpci_dev->dev_list[slot])) { |
Konrad Rzeszutek Wilk | a92336a | 2011-07-19 19:40:51 -0400 | [diff] [blame] | 117 | printk(KERN_INFO DRV_NAME |
| 118 | ": vpci: %s: assign to virtual slot %d\n", |
Konrad Rzeszutek Wilk | 30edc14 | 2009-10-13 17:22:20 -0400 | [diff] [blame] | 119 | pci_name(dev), slot); |
| 120 | list_add_tail(&dev_entry->list, |
| 121 | &vpci_dev->dev_list[slot]); |
| 122 | func = PCI_FUNC(dev->devfn); |
| 123 | goto unlock; |
| 124 | } |
| 125 | } |
| 126 | |
| 127 | err = -ENOMEM; |
| 128 | xenbus_dev_fatal(pdev->xdev, err, |
| 129 | "No more space on root virtual PCI bus"); |
| 130 | |
| 131 | unlock: |
| 132 | spin_unlock_irqrestore(&vpci_dev->lock, flags); |
| 133 | |
| 134 | /* Publish this device. */ |
| 135 | if (!err) |
| 136 | err = publish_cb(pdev, 0, 0, PCI_DEVFN(slot, func), devid); |
| 137 | |
| 138 | out: |
| 139 | return err; |
| 140 | } |
| 141 | |
Konrad Rzeszutek Wilk | 2ebdc42 | 2011-07-11 16:49:41 -0400 | [diff] [blame^] | 142 | static void __xen_pcibk_release_pci_dev(struct xen_pcibk_device *pdev, |
| 143 | struct pci_dev *dev) |
Konrad Rzeszutek Wilk | 30edc14 | 2009-10-13 17:22:20 -0400 | [diff] [blame] | 144 | { |
| 145 | int slot; |
| 146 | struct vpci_dev_data *vpci_dev = pdev->pci_dev_data; |
| 147 | struct pci_dev *found_dev = NULL; |
| 148 | unsigned long flags; |
| 149 | |
| 150 | spin_lock_irqsave(&vpci_dev->lock, flags); |
| 151 | |
| 152 | for (slot = 0; slot < PCI_SLOT_MAX; slot++) { |
| 153 | struct pci_dev_entry *e, *tmp; |
| 154 | list_for_each_entry_safe(e, tmp, &vpci_dev->dev_list[slot], |
| 155 | list) { |
| 156 | if (e->dev == dev) { |
| 157 | list_del(&e->list); |
| 158 | found_dev = e->dev; |
| 159 | kfree(e); |
| 160 | goto out; |
| 161 | } |
| 162 | } |
| 163 | } |
| 164 | |
| 165 | out: |
| 166 | spin_unlock_irqrestore(&vpci_dev->lock, flags); |
| 167 | |
| 168 | if (found_dev) |
| 169 | pcistub_put_pci_dev(found_dev); |
| 170 | } |
| 171 | |
Konrad Rzeszutek Wilk | 2ebdc42 | 2011-07-11 16:49:41 -0400 | [diff] [blame^] | 172 | static int __xen_pcibk_init_devices(struct xen_pcibk_device *pdev) |
Konrad Rzeszutek Wilk | 30edc14 | 2009-10-13 17:22:20 -0400 | [diff] [blame] | 173 | { |
| 174 | int slot; |
| 175 | struct vpci_dev_data *vpci_dev; |
| 176 | |
| 177 | vpci_dev = kmalloc(sizeof(*vpci_dev), GFP_KERNEL); |
| 178 | if (!vpci_dev) |
| 179 | return -ENOMEM; |
| 180 | |
| 181 | spin_lock_init(&vpci_dev->lock); |
| 182 | |
| 183 | for (slot = 0; slot < PCI_SLOT_MAX; slot++) |
| 184 | INIT_LIST_HEAD(&vpci_dev->dev_list[slot]); |
| 185 | |
| 186 | pdev->pci_dev_data = vpci_dev; |
| 187 | |
| 188 | return 0; |
| 189 | } |
| 190 | |
Konrad Rzeszutek Wilk | 2ebdc42 | 2011-07-11 16:49:41 -0400 | [diff] [blame^] | 191 | static int __xen_pcibk_publish_pci_roots(struct xen_pcibk_device *pdev, |
| 192 | publish_pci_root_cb publish_cb) |
Konrad Rzeszutek Wilk | 30edc14 | 2009-10-13 17:22:20 -0400 | [diff] [blame] | 193 | { |
| 194 | /* The Virtual PCI bus has only one root */ |
| 195 | return publish_cb(pdev, 0, 0); |
| 196 | } |
| 197 | |
Konrad Rzeszutek Wilk | 2ebdc42 | 2011-07-11 16:49:41 -0400 | [diff] [blame^] | 198 | static void __xen_pcibk_release_devices(struct xen_pcibk_device *pdev) |
Konrad Rzeszutek Wilk | 30edc14 | 2009-10-13 17:22:20 -0400 | [diff] [blame] | 199 | { |
| 200 | int slot; |
| 201 | struct vpci_dev_data *vpci_dev = pdev->pci_dev_data; |
| 202 | |
| 203 | for (slot = 0; slot < PCI_SLOT_MAX; slot++) { |
| 204 | struct pci_dev_entry *e, *tmp; |
| 205 | list_for_each_entry_safe(e, tmp, &vpci_dev->dev_list[slot], |
| 206 | list) { |
| 207 | list_del(&e->list); |
| 208 | pcistub_put_pci_dev(e->dev); |
| 209 | kfree(e); |
| 210 | } |
| 211 | } |
| 212 | |
| 213 | kfree(vpci_dev); |
| 214 | pdev->pci_dev_data = NULL; |
| 215 | } |
| 216 | |
Konrad Rzeszutek Wilk | 2ebdc42 | 2011-07-11 16:49:41 -0400 | [diff] [blame^] | 217 | static int __xen_pcibk_get_pcifront_dev(struct pci_dev *pcidev, |
| 218 | struct xen_pcibk_device *pdev, |
| 219 | unsigned int *domain, unsigned int *bus, |
| 220 | unsigned int *devfn) |
Konrad Rzeszutek Wilk | 30edc14 | 2009-10-13 17:22:20 -0400 | [diff] [blame] | 221 | { |
| 222 | struct pci_dev_entry *entry; |
| 223 | struct pci_dev *dev = NULL; |
| 224 | struct vpci_dev_data *vpci_dev = pdev->pci_dev_data; |
| 225 | unsigned long flags; |
| 226 | int found = 0, slot; |
| 227 | |
| 228 | spin_lock_irqsave(&vpci_dev->lock, flags); |
| 229 | for (slot = 0; slot < PCI_SLOT_MAX; slot++) { |
| 230 | list_for_each_entry(entry, |
| 231 | &vpci_dev->dev_list[slot], |
| 232 | list) { |
| 233 | dev = entry->dev; |
| 234 | if (dev && dev->bus->number == pcidev->bus->number |
| 235 | && pci_domain_nr(dev->bus) == |
| 236 | pci_domain_nr(pcidev->bus) |
| 237 | && dev->devfn == pcidev->devfn) { |
| 238 | found = 1; |
| 239 | *domain = 0; |
| 240 | *bus = 0; |
| 241 | *devfn = PCI_DEVFN(slot, |
| 242 | PCI_FUNC(pcidev->devfn)); |
| 243 | } |
| 244 | } |
| 245 | } |
| 246 | spin_unlock_irqrestore(&vpci_dev->lock, flags); |
| 247 | return found; |
| 248 | } |
Konrad Rzeszutek Wilk | 2ebdc42 | 2011-07-11 16:49:41 -0400 | [diff] [blame^] | 249 | |
| 250 | struct xen_pcibk_backend xen_pcibk_vpci_backend = { |
| 251 | .name = "vpci", |
| 252 | .init = __xen_pcibk_init_devices, |
| 253 | .free = __xen_pcibk_release_devices, |
| 254 | .find = __xen_pcibk_get_pcifront_dev, |
| 255 | .publish = __xen_pcibk_publish_pci_roots, |
| 256 | .release = __xen_pcibk_release_pci_dev, |
| 257 | .add = __xen_pcibk_add_pci_dev, |
| 258 | .get = __xen_pcibk_get_pci_dev, |
| 259 | }; |