Re: [PATCH 2/2] pci-assign: Use pci_device_set_intx_routing_notifier

[Alex Williamson <alex.williamson@redhat.com>]

On Fri, 2012-08-03 at 12:52 +0200, Jan Kiszka wrote:
> From: Jan Kiszka <jan.kiszka@siemens.com>
> 
> Replace the hack in pci_default_write_config with upstream's generic
> callback mechanism to get informed about changes on the PCI INTx
> routing.
> 
> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
> ---
>  hw/Makefile.objs       |    3 +--
>  hw/device-assignment.c |   48 ++++++++++++++++--------------------------------
>  hw/device-assignment.h |   33 ---------------------------------
>  hw/pc.h                |    3 ---
>  hw/pci.c               |   11 -----------
>  hw/piix_pci.c          |    3 ---
>  6 files changed, 17 insertions(+), 84 deletions(-)
>  delete mode 100644 hw/device-assignment.h
> 
> diff --git a/hw/Makefile.objs b/hw/Makefile.objs
> index 30f9ba6..fa8bb08 100644
> --- a/hw/Makefile.objs
> +++ b/hw/Makefile.objs
> @@ -3,7 +3,7 @@ hw-obj-y += loader.o
>  hw-obj-$(CONFIG_VIRTIO) += virtio-console.o
>  hw-obj-$(CONFIG_VIRTIO_PCI) += virtio-pci.o
>  hw-obj-y += fw_cfg.o
> -hw-obj-$(CONFIG_PCI) += pci_bridge.o pci_bridge_dev.o
> +hw-obj-$(CONFIG_PCI) += pci.o pci_bridge.o pci_bridge_dev.o
>  hw-obj-$(CONFIG_PCI) += msix.o msi.o
>  hw-obj-$(CONFIG_PCI) += shpc.o
>  hw-obj-$(CONFIG_PCI) += slotid_cap.o
> @@ -164,7 +164,6 @@ obj-$(CONFIG_SOFTMMU) += vhost_net.o
>  obj-$(CONFIG_VHOST_NET) += vhost.o
>  obj-$(CONFIG_REALLY_VIRTFS) += 9pfs/
>  obj-$(CONFIG_NO_PCI) += pci-stub.o
> -obj-$(CONFIG_PCI) += pci.o
>  obj-$(CONFIG_VGA) += vga.o
>  obj-$(CONFIG_SOFTMMU) += device-hotplug.o
>  obj-$(CONFIG_XEN) += xen_domainbuild.o xen_machine_pv.o
> diff --git a/hw/device-assignment.c b/hw/device-assignment.c
> index d14c327..7a90027 100644
> --- a/hw/device-assignment.c
> +++ b/hw/device-assignment.c
> @@ -36,7 +36,6 @@
>  #include "pc.h"
>  #include "qemu-error.h"
>  #include "console.h"
> -#include "device-assignment.h"
>  #include "loader.h"
>  #include "monitor.h"
>  #include "range.h"
> @@ -143,6 +142,8 @@ typedef struct AssignedDevice {
>      QLIST_ENTRY(AssignedDevice) next;
>  } AssignedDevice;
>  
> +static void assigned_dev_update_irq_routing(PCIDevice *dev);
> +
>  static void assigned_dev_load_option_rom(AssignedDevice *dev);
>  
>  static void assigned_dev_unregister_msix_mmio(AssignedDevice *dev);
> @@ -869,8 +870,13 @@ static int assign_irq(AssignedDevice *dev)
>      int r = 0;
>  
>      /* Interrupt PIN 0 means don't use INTx */
> -    if (assigned_dev_pci_read_byte(&dev->dev, PCI_INTERRUPT_PIN) == 0)
> +    if (assigned_dev_pci_read_byte(&dev->dev, PCI_INTERRUPT_PIN) == 0) {
> +        pci_device_set_intx_routing_notifier(&dev->dev, NULL);
>          return 0;
> +    }
> +
> +    pci_device_set_intx_routing_notifier(&dev->dev,
> +                                         assigned_dev_update_irq_routing);
>  
>      intx_route = pci_device_route_intx_to_irq(&dev->dev, 0);
>      assert(intx_route.mode != PCI_INTX_INVERTED);
> @@ -944,43 +950,19 @@ static void deassign_device(AssignedDevice *dev)
>                  dev->dev.qdev.id, strerror(-r));
>  }
>  
> -#if 0
> -AssignedDevInfo *get_assigned_device(int pcibus, int slot)
> -{
> -    AssignedDevice *assigned_dev = NULL;
> -    AssignedDevInfo *adev = NULL;
> -
> -    QLIST_FOREACH(adev, &adev_head, next) {
> -        assigned_dev = adev->assigned_dev;
> -        if (pci_bus_num(assigned_dev->dev.bus) == pcibus &&
> -            PCI_SLOT(assigned_dev->dev.devfn) == slot)
> -            return adev;
> -    }
> -
> -    return NULL;
> -}
> -#endif
> -
>  /* The pci config space got updated. Check if irq numbers have changed
>   * for our devices
>   */
> -void assigned_dev_update_irqs(void)
> +static void assigned_dev_update_irq_routing(PCIDevice *dev)
>  {
> -    AssignedDevice *dev, *next;
> +    AssignedDevice *assigned_dev = DO_UPCAST(AssignedDevice, dev, dev);
>      Error *err = NULL;
>      int r;
>  
> -    dev = QLIST_FIRST(&devs);
> -    while (dev) {
> -        next = QLIST_NEXT(dev, next);
> -        if (dev->irq_requested_type & KVM_DEV_IRQ_HOST_INTX) {
> -            r = assign_irq(dev);
> -            if (r < 0) {
> -                qdev_unplug(&dev->dev.qdev, &err);
> -                assert(!err);
> -            }
> -        }
> -        dev = next;
> +    r = assign_irq(assigned_dev);
> +    if (r < 0) {
> +        qdev_unplug(&dev->qdev, &err);
> +        assert(!err);
>      }
>  }
>  
> @@ -1009,6 +991,7 @@ static void assigned_dev_update_msi(PCIDevice *pci_dev)
>              perror("assigned_dev_update_msi: deassign irq");
>  
>          assigned_dev->irq_requested_type = 0;
> +        pci_device_set_intx_routing_notifier(pci_dev, NULL);
>      }
>  
>      if (ctrl_byte & PCI_MSI_FLAGS_ENABLE) {
> @@ -1151,6 +1134,7 @@ static void assigned_dev_update_msix(PCIDevice *pci_dev)
>              perror("assigned_dev_update_msix: deassign irq");
>  
>          assigned_dev->irq_requested_type = 0;
> +        pci_device_set_intx_routing_notifier(pci_dev, NULL);
>      }
>  
>      if (ctrl_word & PCI_MSIX_FLAGS_ENABLE) {
> diff --git a/hw/device-assignment.h b/hw/device-assignment.h
> deleted file mode 100644
> index 3fcb804..0000000
> --- a/hw/device-assignment.h
> +++ /dev/null
> @@ -1,33 +0,0 @@
> -/*
> - * Copyright (c) 2007, Neocleus Corporation.
> - * Copyright (c) 2007, Intel Corporation.
> - *
> - * This program is free software; you can redistribute it and/or modify it
> - * under the terms and conditions of the GNU General Public License,
> - * version 2, as published by the Free Software Foundation.
> - *
> - * This program is distributed in the hope 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, write to the Free Software Foundation, Inc., 59 Temple
> - * Place - Suite 330, Boston, MA 02111-1307 USA.
> - *
> - *  Data structures for storing PCI state
> - *
> - *  Adapted to kvm by Qumranet
> - *
> - *  Copyright (c) 2007, Neocleus, Alex Novik (alex@neocleus.com)
> - *  Copyright (c) 2007, Neocleus, Guy Zana (guy@neocleus.com)
> - *  Copyright (C) 2008, Qumranet, Amit Shah (amit.shah@qumranet.com)
> - *  Copyright (C) 2008, Red Hat, Amit Shah (amit.shah@redhat.com)
> - */
> -
> -#ifndef __DEVICE_ASSIGNMENT_H__
> -#define __DEVICE_ASSIGNMENT_H__
> -
> -void assigned_dev_update_irqs(void);
> -
> -#endif              /* __DEVICE_ASSIGNMENT_H__ */
> diff --git a/hw/pc.h b/hw/pc.h
> index 5b36eb5..31ccb6f 100644
> --- a/hw/pc.h
> +++ b/hw/pc.h
> @@ -149,9 +149,6 @@ void piix4_smbus_register_device(SMBusDevice *dev, uint8_t addr);
>  extern int no_hpet;
>  
>  /* piix_pci.c */
> -/* config space register for IRQ routing */
> -#define PIIX_CONFIG_IRQ_ROUTE 0x60
> -
>  struct PCII440FXState;
>  typedef struct PCII440FXState PCII440FXState;
>  
> diff --git a/hw/pci.c b/hw/pci.c
> index 0b22913..4d95984 100644
> --- a/hw/pci.c
> +++ b/hw/pci.c
> @@ -29,9 +29,6 @@
>  #include "net.h"
>  #include "sysemu.h"
>  #include "loader.h"
> -#include "hw/pc.h"
> -#include "kvm.h"
> -#include "device-assignment.h"
>  #include "range.h"
>  #include "qmp-commands.h"
>  #include "msi.h"
> @@ -1048,14 +1045,6 @@ void pci_default_write_config(PCIDevice *d, uint32_t addr, uint32_t val, int l)
>          d->config[addr + i] = (d->config[addr + i] & ~wmask) | (val & wmask);
>          d->config[addr + i] &= ~(val & w1cmask); /* W1C: Write 1 to Clear */
>      }
> -
> -#ifdef CONFIG_KVM_DEVICE_ASSIGNMENT
> -    if (kvm_enabled() && kvm_irqchip_in_kernel() &&
> -        addr >= PIIX_CONFIG_IRQ_ROUTE &&
> -	addr < PIIX_CONFIG_IRQ_ROUTE + 4)
> -        assigned_dev_update_irqs();
> -#endif /* CONFIG_KVM_DEVICE_ASSIGNMENT */
> -
>      if (ranges_overlap(addr, l, PCI_BASE_ADDRESS_0, 24) ||
>          ranges_overlap(addr, l, PCI_ROM_ADDRESS, 4) ||
>          ranges_overlap(addr, l, PCI_ROM_ADDRESS1, 4) ||
> diff --git a/hw/piix_pci.c b/hw/piix_pci.c
> index 355814f..c497a01 100644
> --- a/hw/piix_pci.c
> +++ b/hw/piix_pci.c
> @@ -250,8 +250,6 @@ static int i440fx_initfn(PCIDevice *dev)
>      return 0;
>  }
>  
> -static PIIX3State *piix3_dev;
> -
>  static PCIBus *i440fx_common_init(const char *device_name,
>                                    PCII440FXState **pi440fx_state,
>                                    int *piix3_devfn,
> @@ -331,7 +329,6 @@ static PCIBus *i440fx_common_init(const char *device_name,
>          ram_size = 255;
>      (*pi440fx_state)->dev.config[0x57]=ram_size;
>  
> -    piix3_dev = piix3;
>      i440fx_update_memory_mappings(f);
>  
>      return b;

For vfio I chose to leave the intx routing notifier in place for msi &
msix as we can easily ignore it when not using intx.  I don't see much
advantage to one over the other though.

Acked-by: Alex Williamson <alex.williamson@redhat.com>