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 #include <asm/xen/hypervisor.h>
  27 #include <asm/xen/hypercall.h>
  28 #include "../pci/pci.h"
  29
  30 static bool __read_mostly pci_seg_supported = true;
  31
  32 static int xen_add_device(struct device *dev)
  33 {
  34         int r;
  35         struct pci_dev *pci_dev = to_pci_dev(dev);
  36 #ifdef CONFIG_PCI_IOV
  37         struct pci_dev *physfn = pci_dev->physfn;
  38 #endif
  39
  40         if (pci_seg_supported) {
  41                 struct physdev_pci_device_add add = {
  42                         .seg = pci_domain_nr(pci_dev->bus),
  43                         .bus = pci_dev->bus->number,
  44                         .devfn = pci_dev->devfn
  45                 };
  46 #ifdef CONFIG_ACPI
  47                 acpi_handle handle;
  48 #endif
  49
  50 #ifdef CONFIG_PCI_IOV
  51                 if (pci_dev->is_virtfn) {
  52                         add.flags = XEN_PCI_DEV_VIRTFN;
  53                         add.physfn.bus = physfn->bus->number;
  54                         add.physfn.devfn = physfn->devfn;
  55                 } else
  56 #endif
  57                 if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn))
  58                         add.flags = XEN_PCI_DEV_EXTFN;
  59
  60 #ifdef CONFIG_ACPI
  61                 handle = DEVICE_ACPI_HANDLE(&pci_dev->dev);
  62                 if (!handle && pci_dev->bus->bridge)
  63                         handle = DEVICE_ACPI_HANDLE(pci_dev->bus->bridge);
  64 #ifdef CONFIG_PCI_IOV
  65                 if (!handle && pci_dev->is_virtfn)
  66                         handle = DEVICE_ACPI_HANDLE(physfn->bus->bridge);
  67 #endif
  68                 if (handle) {
  69                         acpi_status status;
  70
  71                         do {
  72                                 unsigned long long pxm;
  73
  74                                 status = acpi_evaluate_integer(handle, "_PXM",
  75                                                                NULL, &pxm);
  76                                 if (ACPI_SUCCESS(status)) {
  77                                         add.optarr[0] = pxm;
  78                                         add.flags |= XEN_PCI_DEV_PXM;
  79                                         break;
  80                                 }
  81                                 status = acpi_get_parent(handle, &handle);
  82                         } while (ACPI_SUCCESS(status));
  83                 }
  84 #endif /* CONFIG_ACPI */
  85
  86                 r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_add, &add);
  87                 if (r != -ENOSYS)
  88                         return r;
  89                 pci_seg_supported = false;
  90         }
  91
  92         if (pci_domain_nr(pci_dev->bus))
  93                 r = -ENOSYS;
  94 #ifdef CONFIG_PCI_IOV
  95         else if (pci_dev->is_virtfn) {
  96                 struct physdev_manage_pci_ext manage_pci_ext = {
  97                         .bus            = pci_dev->bus->number,
  98                         .devfn          = pci_dev->devfn,
  99                         .is_virtfn      = 1,
 100                         .physfn.bus     = physfn->bus->number,
 101                         .physfn.devfn   = physfn->devfn,
 102                 };
 103
 104                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
 105                         &manage_pci_ext);
 106         }
 107 #endif
 108         else if (pci_ari_enabled(pci_dev->bus) && PCI_SLOT(pci_dev->devfn)) {
 109                 struct physdev_manage_pci_ext manage_pci_ext = {
 110                         .bus            = pci_dev->bus->number,
 111                         .devfn          = pci_dev->devfn,
 112                         .is_extfn       = 1,
 113                 };
 114
 115                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add_ext,
 116                         &manage_pci_ext);
 117         } else {
 118                 struct physdev_manage_pci manage_pci = {
 119                         .bus    = pci_dev->bus->number,
 120                         .devfn  = pci_dev->devfn,
 121                 };
 122
 123                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_add,
 124                         &manage_pci);
 125         }
 126
 127         return r;
 128 }
 129
 130 static int xen_remove_device(struct device *dev)
 131 {
 132         int r;
 133         struct pci_dev *pci_dev = to_pci_dev(dev);
 134
 135         if (pci_seg_supported) {
 136                 struct physdev_pci_device device = {
 137                         .seg = pci_domain_nr(pci_dev->bus),
 138                         .bus = pci_dev->bus->number,
 139                         .devfn = pci_dev->devfn
 140                 };
 141
 142                 r = HYPERVISOR_physdev_op(PHYSDEVOP_pci_device_remove,
 143                                           &device);
 144         } else if (pci_domain_nr(pci_dev->bus))
 145                 r = -ENOSYS;
 146         else {
 147                 struct physdev_manage_pci manage_pci = {
 148                         .bus = pci_dev->bus->number,
 149                         .devfn = pci_dev->devfn
 150                 };
 151
 152                 r = HYPERVISOR_physdev_op(PHYSDEVOP_manage_pci_remove,
 153                                           &manage_pci);
 154         }
 155
 156         return r;
 157 }
 158
 159 static int xen_pci_notifier(struct notifier_block *nb,
 160                             unsigned long action, void *data)
 161 {
 162         struct device *dev = data;
 163         int r = 0;
 164
 165         switch (action) {
 166         case BUS_NOTIFY_ADD_DEVICE:
 167                 r = xen_add_device(dev);
 168                 break;
 169         case BUS_NOTIFY_DEL_DEVICE:
 170                 r = xen_remove_device(dev);
 171                 break;
 172         default:
 173                 return NOTIFY_DONE;
 174         }
 175         if (r)
 176                 dev_err(dev, "Failed to %s - passthrough or MSI/MSI-X might fail!\n",
 177                         action == BUS_NOTIFY_ADD_DEVICE ? "add" :
 178                         (action == BUS_NOTIFY_DEL_DEVICE ? "delete" : "?"));
 179         return NOTIFY_OK;
 180 }
 181
 182 static struct notifier_block device_nb = {
 183         .notifier_call = xen_pci_notifier,
 184 };
 185
 186 static int __init register_xen_pci_notifier(void)
 187 {
 188         if (!xen_initial_domain())
 189                 return 0;
 190
 191         return bus_register_notifier(&pci_bus_type, &device_nb);
 192 }
 193
 194 arch_initcall(register_xen_pci_notifier);