qemu

spapr_pci_vfio.c (6537B)

---

 /*
  * QEMU sPAPR PCI host for VFIO
  *
  * Copyright (c) 2011-2014 Alexey Kardashevskiy, IBM Corporation.
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
  *  the Free Software Foundation; either version 2 of the License,
  *  or (at your option) any later version.
  *
  *  This program is distributed in the hope that it will be useful,
  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  *  GNU General Public License for more details.
  *
  *  You should have received a copy of the GNU General Public License
  *  along with this program; if not, see <http://www.gnu.org/licenses/>.
  */
 
 #include "qemu/osdep.h"
 #include <linux/vfio.h>
 #include "hw/ppc/spapr.h"
 #include "hw/pci-host/spapr.h"
 #include "hw/pci/msix.h"
 #include "hw/vfio/vfio.h"
 #include "qemu/error-report.h"
 
 bool spapr_phb_eeh_available(SpaprPhbState *sphb)
 {
     return vfio_eeh_as_ok(&sphb->iommu_as);
 }
 
 static void spapr_phb_vfio_eeh_reenable(SpaprPhbState *sphb)
 {
     vfio_eeh_as_op(&sphb->iommu_as, VFIO_EEH_PE_ENABLE);
 }
 
 void spapr_phb_vfio_reset(DeviceState *qdev)
 {
     /*
      * The PE might be in frozen state. To reenable the EEH
      * functionality on it will clean the frozen state, which
      * ensures that the contained PCI devices will work properly
      * after reboot.
      */
     spapr_phb_vfio_eeh_reenable(SPAPR_PCI_HOST_BRIDGE(qdev));
 }
 
 static void spapr_eeh_pci_find_device(PCIBus *bus, PCIDevice *pdev,
                                       void *opaque)
 {
     bool *found = opaque;
 
     if (object_dynamic_cast(OBJECT(pdev), "vfio-pci")) {
         *found = true;
     }
 }
 
 int spapr_phb_vfio_eeh_set_option(SpaprPhbState *sphb,
                                   unsigned int addr, int option)
 {
     uint32_t op;
     int ret;
 
     switch (option) {
     case RTAS_EEH_DISABLE:
         op = VFIO_EEH_PE_DISABLE;
         break;
     case RTAS_EEH_ENABLE: {
         PCIHostState *phb;
         bool found = false;
 
         /*
          * The EEH functionality is enabled per sphb level instead of
          * per PCI device. We have already identified this specific sphb
          * based on buid passed as argument to ibm,set-eeh-option rtas
          * call. Now we just need to check the validity of the PCI
          * pass-through devices (vfio-pci) under this sphb bus.
          * We have already validated that all the devices under this sphb
          * are from same iommu group (within same PE) before comming here.
          *
          * Prior to linux commit 98ba956f6a389 ("powerpc/pseries/eeh:
          * Rework device EEH PE determination") kernel would call
          * eeh-set-option for each device in the PE using the device's
          * config_address as the argument rather than the PE address.
          * Hence if we check validity of supplied config_addr whether
          * it matches to this PHB will cause issues with older kernel
          * versions v5.9 and older. If we return an error from
          * eeh-set-option when the argument isn't a valid PE address
          * then older kernels (v5.9 and older) will interpret that as
          * EEH not being supported.
          */
         phb = PCI_HOST_BRIDGE(sphb);
         pci_for_each_device(phb->bus, (addr >> 16) & 0xFF,
                             spapr_eeh_pci_find_device, &found);
 
         if (!found) {
             return RTAS_OUT_PARAM_ERROR;
         }
 
         op = VFIO_EEH_PE_ENABLE;
         break;
     }
     case RTAS_EEH_THAW_IO:
         op = VFIO_EEH_PE_UNFREEZE_IO;
         break;
     case RTAS_EEH_THAW_DMA:
         op = VFIO_EEH_PE_UNFREEZE_DMA;
         break;
     default:
         return RTAS_OUT_PARAM_ERROR;
     }
 
     ret = vfio_eeh_as_op(&sphb->iommu_as, op);
     if (ret < 0) {
         return RTAS_OUT_HW_ERROR;
     }
 
     return RTAS_OUT_SUCCESS;
 }
 
 int spapr_phb_vfio_eeh_get_state(SpaprPhbState *sphb, int *state)
 {
     int ret;
 
     ret = vfio_eeh_as_op(&sphb->iommu_as, VFIO_EEH_PE_GET_STATE);
     if (ret < 0) {
         return RTAS_OUT_PARAM_ERROR;
     }
 
     *state = ret;
     return RTAS_OUT_SUCCESS;
 }
 
 static void spapr_phb_vfio_eeh_clear_dev_msix(PCIBus *bus,
                                               PCIDevice *pdev,
                                               void *opaque)
 {
     /* Check if the device is VFIO PCI device */
     if (!object_dynamic_cast(OBJECT(pdev), "vfio-pci")) {
         return;
     }
 
     /*
      * The MSIx table will be cleaned out by reset. We need
      * disable it so that it can be reenabled properly. Also,
      * the cached MSIx table should be cleared as it's not
      * reflecting the contents in hardware.
      */
     if (msix_enabled(pdev)) {
         uint16_t flags;
 
         flags = pci_host_config_read_common(pdev,
                                             pdev->msix_cap + PCI_MSIX_FLAGS,
                                             pci_config_size(pdev), 2);
         flags &= ~PCI_MSIX_FLAGS_ENABLE;
         pci_host_config_write_common(pdev,
                                      pdev->msix_cap + PCI_MSIX_FLAGS,
                                      pci_config_size(pdev), flags, 2);
     }
 
     msix_reset(pdev);
 }
 
 static void spapr_phb_vfio_eeh_clear_bus_msix(PCIBus *bus, void *opaque)
 {
        pci_for_each_device_under_bus(bus, spapr_phb_vfio_eeh_clear_dev_msix,
                                      NULL);
 }
 
 static void spapr_phb_vfio_eeh_pre_reset(SpaprPhbState *sphb)
 {
        PCIHostState *phb = PCI_HOST_BRIDGE(sphb);
 
        pci_for_each_bus(phb->bus, spapr_phb_vfio_eeh_clear_bus_msix, NULL);
 }
 
 int spapr_phb_vfio_eeh_reset(SpaprPhbState *sphb, int option)
 {
     uint32_t op;
     int ret;
 
     switch (option) {
     case RTAS_SLOT_RESET_DEACTIVATE:
         op = VFIO_EEH_PE_RESET_DEACTIVATE;
         break;
     case RTAS_SLOT_RESET_HOT:
         spapr_phb_vfio_eeh_pre_reset(sphb);
         op = VFIO_EEH_PE_RESET_HOT;
         break;
     case RTAS_SLOT_RESET_FUNDAMENTAL:
         spapr_phb_vfio_eeh_pre_reset(sphb);
         op = VFIO_EEH_PE_RESET_FUNDAMENTAL;
         break;
     default:
         return RTAS_OUT_PARAM_ERROR;
     }
 
     ret = vfio_eeh_as_op(&sphb->iommu_as, op);
     if (ret < 0) {
         return RTAS_OUT_HW_ERROR;
     }
 
     return RTAS_OUT_SUCCESS;
 }
 
 int spapr_phb_vfio_eeh_configure(SpaprPhbState *sphb)
 {
     int ret;
 
     ret = vfio_eeh_as_op(&sphb->iommu_as, VFIO_EEH_PE_CONFIGURE);
     if (ret < 0) {
         return RTAS_OUT_PARAM_ERROR;
     }
 
     return RTAS_OUT_SUCCESS;
 }