drivers/xen/pci.c

   1 /*
   2  * Copyright (c) 2009, Intel Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
  15  * Place - Suite 330, Boston, MA 02111-1307 USA.
  16  *
  17  * Author: Weidong Han <weidong.han@intel.com>
  18  */
  19
  20 #include <linux/pci.h>
  21 #include <linux/acpi.h>
  22 #include <xen/xen.h>
  23 #include <xen/interface/physdev.h>
  24 #include <xen/interface/xen.h>
  25
  26 #ifdef CONFIG_PARAVIRT_XEN
  27 #define CONFIG_XEN_COMPAT 0x040000
  28 #include <asm/xen/hypervisor.h>
  29 #include <asm/xen/hypercall.h>
  30 #else
  31 #include <asm/hypervisor.h>
  32 #endif
  33 #include "../pci/pci.h"
  34
  35 #if CONFIG_XEN_COMPAT < 0x040200
  36 static bool __read_mostly pci_seg_supported = true;
  37 #else
  38 #define pci_seg_supported true
  39 #endif
  40
  41 static int xen_add_device(struct device *dev)
  42 {
  43         int r;
  44         struct pci_dev *pci_dev = to_pci_dev(dev);
  45 #ifdef CONFIG_PCI_IOV
  46         struct pci_dev *physfn = pci_dev->physfn;
  47 #endif
  48
  49         if (pci_seg_supported) {
  50                 struct physdev_pci_device_add add = {
  51                         .seg = pci_domain_nr(pci_dev->bus),
  52                         .bus = pci_dev->bus->number,
  53                         .devfn = pci_dev->devfn
  54                 };
  55 #ifdef CONFIG_ACPI
  56                 acpi_handle handle;
  57 #endif
  58
  59 #ifdef CONFIG_PCI_IOV
  60                 if (pci_dev->is_virtfn) {
  61                         add.flags = XEN_PCI_DEV_VIRTFN;
  62                         add.physfn.bus = physfn->bus->number;
  63                         add.physfn.devfn = physfn->devfn;
  64                 } else
  65 #endif
  66                 if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn))
  67                         add.flags = XEN_PCI_DEV_EXTFN;
  68
  69 #ifdef CONFIG_ACPI
  70                 handle = DEVICE_ACPI_HANDLE(&pci_dev->dev);
  71                 if (!handle)
  72                         handle = DEVICE_ACPI_HANDLE(pci_dev->bus->bridge);
  73 #ifdef CONFIG_PCI_IOV
  74                 if (!handle && pci_dev->is_virtfn)
  75                         handle = DEVICE_ACPI_HANDLE(physfn->bus->bridge);
  76 #endif
  77                 if (handle) {
  78                         acpi_status status;
  79
  80                         do {
  81                                 unsigned long long pxm;
  82
  83                                 status = acpi_evaluate_integer(handle, "_PXM",
  84                                                                NULL, &pxm);
  85                                 if (ACPI_SUCCESS(status)) {
  86                                         add.optarr[0] = pxm;
  87                                         add.flags |= XEN_PCI_DEV_PXM;
  88                                         break;
  89                                 }
  90                                 status = acpi_get_parent(handle, &handle);
  91                         } while (ACPI_SUCCESS(status));
  92                 }
  93 #endif /* CONFIG_ACPI */
  94
  95                 r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_add, &add);
  96                 if (r != -ENOSYS)
  97                         return r;
  98 #if CONFIG_XEN_COMPAT < 0x040200
  99                 pci_seg_supported = false;
 100 #endif
 101         }
 102
 103         if (pci_domain_nr(pci_dev->bus))
 104                 r = -ENOSYS;
 105 #ifdef CONFIG_PCI_IOV
 106         else if (pci_dev->is_virtfn) {
 107                 struct physdev_manage_pci_ext manage_pci_ext = {
 108                         .bus            = pci_dev->bus->number,
 109                         .devfn          = pci_dev->devfn,
 110                         .is_virtfn      = 1,
 111                         .physfn.bus     = physfn->bus->number,
 112                         .physfn.devfn   = physfn->devfn,
 113                 };
 114
 115                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
 116                         &manage_pci_ext);
 117         }
 118 #endif
 119         else if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn)) {
 120                 struct physdev_manage_pci_ext manage_pci_ext = {
 121                         .bus            = pci_dev->bus->number,
 122                         .devfn          = pci_dev->devfn,
 123                         .is_extfn       = 1,
 124                 };
 125
 126                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
 127                         &manage_pci_ext);
 128         } else {
 129                 struct physdev_manage_pci manage_pci = {
 130                         .bus    = pci_dev->bus->number,
 131                         .devfn  = pci_dev->devfn,
 132                 };
 133
 134                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add,
 135                         &manage_pci);
 136         }
 137
 138         return r;
 139 }
 140
 141 static int xen_remove_device(struct device *dev)
 142 {
 143         int r;
 144         struct pci_dev *pci_dev = to_pci_dev(dev);
 145
 146         if (pci_seg_supported) {
 147                 struct physdev_pci_device device = {
 148                         .seg = pci_domain_nr(pci_dev->bus),
 149                         .bus = pci_dev->bus->number,
 150                         .devfn = pci_dev->devfn
 151                 };
 152
 153                 r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_remove,
 154                                           &device);
 155         } else if (pci_domain_nr(pci_dev->bus))
 156                 r = -ENOSYS;
 157         else {
 158                 struct physdev_manage_pci manage_pci = {
 159                         .bus = pci_dev->bus->number,
 160                         .devfn = pci_dev->devfn
 161                 };
 162
 163                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_remove,
 164                                           &manage_pci);
 165         }
 166
 167         return r;
 168 }
 169
 170 static int xen_pci_notifier(struct notifier_block *nb,
 171                             unsigned long action, void *data)
 172 {
 173         struct device *dev = data;
 174         int r = 0;
 175
 176         switch (action) {
 177         case BUS_NOTIFY_ADD_DEVICE:
 178                 r = xen_add_device(dev);
 179                 break;
 180         case BUS_NOTIFY_DEL_DEVICE:
 181                 r = xen_remove_device(dev);
 182                 break;
 183         default:
 184                 return NOTIFY_DONE;
 185         }
 186         if (r)
 187                 dev_err(dev, "Failed to %s - passthrough or MSI/MSI-X might fail!\n",
 188                         action == BUS_NOTIFY_ADD_DEVICE ? "add" :
 189                         (action == BUS_NOTIFY_DEL_DEVICE ? "delete" : "?"));
 190         return NOTIFY_OK;
 191 }
 192
 193 static struct notifier_block device_nb = {
 194         .notifier_call = xen_pci_notifier,
 195 };
 196
 197 static int __init register_xen_pci_notifier(void)
 198 {
 199         if (!xen_initial_domain())
 200                 return 0;
 201
 202         return bus_register_notifier(&pci_bus_type, &device_nb);
 203 }
 204
 205 arch_initcall(register_xen_pci_notifier);