qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [PATCH V8 27/39] vfio-pci: cpr part 1 (fd and dma)


From: Alex Williamson
Subject: Re: [PATCH V8 27/39] vfio-pci: cpr part 1 (fd and dma)
Date: Wed, 29 Jun 2022 13:14:55 -0600

On Wed, 15 Jun 2022 07:52:14 -0700
Steve Sistare <steven.sistare@oracle.com> wrote:

> Enable vfio-pci devices to be saved and restored across an exec restart
> of qemu.
> 
> At vfio creation time, save the value of vfio container, group, and device
> descriptors in cpr state.
> 
> In the container pre_save handler, suspend the use of virtual addresses in
> DMA mappings with VFIO_DMA_UNMAP_FLAG_VADDR, because guest ram will be
> remapped at a different VA after exec.  DMA to already-mapped pages
> continues.  Save the msi message area as part of vfio-pci vmstate, save the
> interrupt and notifier eventfd's in cpr state, and clear the close-on-exec
> flag for the vfio descriptors.  The flag is not cleared earlier because the
> descriptors should not persist across miscellaneous fork and exec calls
> that may be performed during normal operation.
> 
> On qemu restart, vfio_realize() finds the saved descriptors, uses
> the descriptors, and notes that the device is being reused.  Device and
> iommu state is already configured, so operations in vfio_realize that
> would modify the configuration are skipped for a reused device, including
> vfio ioctl's and writes to PCI configuration space.  Vfio PCI device reset
> is also suppressed. The result is that vfio_realize constructs qemu data
> structures that reflect the current state of the device.  However, the
> reconstruction is not complete until cpr-load is called. cpr-load loads the
> msi data.  The vfio post_load handler finds eventfds in cpr state, rebuilds
> vector data structures, and attaches the interrupts to the new KVM instance.
> The container post_load handler then invokes the main vfio listener
> callback, which walks the flattened ranges of the vfio address space and
> calls VFIO_DMA_MAP_FLAG_VADDR to inform the kernel of the new VA's.  Lastly,
> cpr-load starts the VM.
> 
> This functionality is delivered by 3 patches for clarity.  Part 1 handles
> device file descriptors and DMA.  Part 2 adds eventfd and MSI/MSI-X vector
> support.  Part 3 adds INTX support.
> 
> Signed-off-by: Steve Sistare <steven.sistare@oracle.com>
> ---
>  MAINTAINERS                   |   1 +
>  hw/pci/pci.c                  |  12 ++++
>  hw/vfio/common.c              | 151 
> +++++++++++++++++++++++++++++++++++-------
>  hw/vfio/cpr.c                 | 119 +++++++++++++++++++++++++++++++++
>  hw/vfio/meson.build           |   1 +
>  hw/vfio/pci.c                 |  44 ++++++++++++
>  hw/vfio/trace-events          |   1 +
>  include/hw/vfio/vfio-common.h |  11 +++
>  include/migration/vmstate.h   |   1 +
>  9 files changed, 317 insertions(+), 24 deletions(-)
>  create mode 100644 hw/vfio/cpr.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 74a43e6..864aec6 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -3156,6 +3156,7 @@ CPR
>  M: Steve Sistare <steven.sistare@oracle.com>
>  M: Mark Kanda <mark.kanda@oracle.com>
>  S: Maintained
> +F: hw/vfio/cpr.c
>  F: include/migration/cpr.h
>  F: migration/cpr.c
>  F: qapi/cpr.json
> diff --git a/hw/pci/pci.c b/hw/pci/pci.c
> index 6e70153..a3b19eb 100644
> --- a/hw/pci/pci.c
> +++ b/hw/pci/pci.c
> @@ -32,6 +32,7 @@
>  #include "hw/pci/pci_host.h"
>  #include "hw/qdev-properties.h"
>  #include "hw/qdev-properties-system.h"
> +#include "migration/cpr.h"
>  #include "migration/qemu-file-types.h"
>  #include "migration/vmstate.h"
>  #include "monitor/monitor.h"
> @@ -341,6 +342,17 @@ static void pci_reset_regions(PCIDevice *dev)
>  
>  static void pci_do_device_reset(PCIDevice *dev)
>  {
> +    /*
> +     * A PCI device that is resuming for cpr is already configured, so do
> +     * not reset it here when we are called from qemu_system_reset prior to
> +     * cpr-load, else interrupts may be lost for vfio-pci devices.  It is
> +     * safe to skip this reset for all PCI devices, because cpr-load will set
> +     * all fields that would have been set here.
> +     */
> +    if (cpr_get_mode() == CPR_MODE_RESTART) {
> +        return;
> +    }
> +
>      pci_device_deassert_intx(dev);
>      assert(dev->irq_state == 0);
>  
> diff --git a/hw/vfio/common.c b/hw/vfio/common.c
> index ace9562..c7d73b6 100644
> --- a/hw/vfio/common.c
> +++ b/hw/vfio/common.c
> @@ -31,6 +31,7 @@
>  #include "exec/memory.h"
>  #include "exec/ram_addr.h"
>  #include "hw/hw.h"
> +#include "migration/cpr.h"
>  #include "qemu/error-report.h"
>  #include "qemu/main-loop.h"
>  #include "qemu/range.h"
> @@ -460,6 +461,8 @@ static int vfio_dma_unmap(VFIOContainer *container,
>          .size = size,
>      };
>  
> +    assert(!container->reused);
> +
>      if (iotlb && container->dirty_pages_supported &&
>          vfio_devices_all_running_and_saving(container)) {
>          return vfio_dma_unmap_bitmap(container, iova, size, iotlb);
> @@ -496,12 +499,24 @@ static int vfio_dma_map(VFIOContainer *container, 
> hwaddr iova,
>  {
>      struct vfio_iommu_type1_dma_map map = {
>          .argsz = sizeof(map),
> -        .flags = VFIO_DMA_MAP_FLAG_READ,
>          .vaddr = (__u64)(uintptr_t)vaddr,
>          .iova = iova,
>          .size = size,
>      };
>  
> +    /*
> +     * Set the new vaddr for any mappings registered during cpr-load.
> +     * Reused is cleared thereafter.
> +     */
> +    if (container->reused) {
> +        map.flags = VFIO_DMA_MAP_FLAG_VADDR;
> +        if (ioctl(container->fd, VFIO_IOMMU_MAP_DMA, &map)) {
> +            goto fail;
> +        }
> +        return 0;
> +    }
> +
> +    map.flags = VFIO_DMA_MAP_FLAG_READ;
>      if (!readonly) {
>          map.flags |= VFIO_DMA_MAP_FLAG_WRITE;
>      }
> @@ -517,7 +532,9 @@ static int vfio_dma_map(VFIOContainer *container, hwaddr 
> iova,
>          return 0;
>      }
>  
> -    error_report("VFIO_MAP_DMA failed: %s", strerror(errno));
> +fail:
> +    error_report("vfio_dma_map %s (iova %lu, size %ld, va %p): %s",
> +        (container->reused ? "VADDR" : ""), iova, size, vaddr, 
> strerror(errno));
>      return -errno;
>  }
>  
> @@ -882,6 +899,12 @@ static void vfio_listener_region_add(MemoryListener 
> *listener,
>                                       MemoryRegionSection *section)
>  {
>      VFIOContainer *container = container_of(listener, VFIOContainer, 
> listener);
> +    vfio_container_region_add(container, section);
> +}
> +
> +void vfio_container_region_add(VFIOContainer *container,
> +                               MemoryRegionSection *section)
> +{
>      hwaddr iova, end;
>      Int128 llend, llsize;
>      void *vaddr;
> @@ -1492,6 +1515,12 @@ static void vfio_listener_release(VFIOContainer 
> *container)
>      }
>  }
>  
> +void vfio_listener_register(VFIOContainer *container)
> +{
> +    container->listener = vfio_memory_listener;
> +    memory_listener_register(&container->listener, container->space->as);
> +}
> +
>  static struct vfio_info_cap_header *
>  vfio_get_cap(void *ptr, uint32_t cap_offset, uint16_t id)
>  {
> @@ -1910,6 +1939,22 @@ static int vfio_init_container(VFIOContainer 
> *container, int group_fd,
>  {
>      int iommu_type, ret;
>  
> +    /*
> +     * If container is reused, just set its type and skip the ioctls, as the
> +     * container and group are already configured in the kernel.
> +     * VFIO_TYPE1v2_IOMMU is the only type that supports reuse/cpr.
> +     */
> +    if (container->reused) {
> +        if (ioctl(container->fd, VFIO_CHECK_EXTENSION, VFIO_TYPE1v2_IOMMU)) {
> +            container->iommu_type = VFIO_TYPE1v2_IOMMU;
> +            return 0;
> +        } else {
> +            error_setg(errp, "container was reused but VFIO_TYPE1v2_IOMMU "
> +                             "is not supported");
> +            return -errno;
> +        }
> +    }
> +
>      iommu_type = vfio_get_iommu_type(container, errp);
>      if (iommu_type < 0) {
>          return iommu_type;
> @@ -2014,9 +2059,12 @@ static int vfio_connect_container(VFIOGroup *group, 
> AddressSpace *as,
>  {
>      VFIOContainer *container;
>      int ret, fd;
> +    bool reused;
>      VFIOAddressSpace *space;
>  
>      space = vfio_get_address_space(as);
> +    fd = cpr_find_fd("vfio_container_for_group", group->groupid);
> +    reused = (fd > 0);
>  
>      /*
>       * VFIO is currently incompatible with discarding of RAM insofar as the
> @@ -2049,27 +2097,47 @@ static int vfio_connect_container(VFIOGroup *group, 
> AddressSpace *as,
>       * details once we know which type of IOMMU we are using.
>       */
>  
> +    /*
> +     * If the container is reused, then the group is already attached in the
> +     * kernel.  If a container with matching fd is found, then update the
> +     * userland group list and return.  If not, then after the loop, create
> +     * the container struct and group list.
> +     */
> +
>      QLIST_FOREACH(container, &space->containers, next) {
> -        if (!ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, &container->fd)) {
> -            ret = vfio_ram_block_discard_disable(container, true);
> -            if (ret) {
> -                error_setg_errno(errp, -ret,
> -                                 "Cannot set discarding of RAM broken");
> -                if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER,
> -                          &container->fd)) {
> -                    error_report("vfio: error disconnecting group %d from"
> -                                 " container", group->groupid);
> -                }
> -                return ret;
> +        if (reused) {
> +            if (container->fd != fd) {
> +                continue;
>              }
> -            group->container = container;
> -            QLIST_INSERT_HEAD(&container->group_list, group, container_next);
> +        } else if (ioctl(group->fd, VFIO_GROUP_SET_CONTAINER, 
> &container->fd)) {
> +            continue;
> +        }
> +
> +        ret = vfio_ram_block_discard_disable(container, true);
> +        if (ret) {
> +            error_setg_errno(errp, -ret,
> +                             "Cannot set discarding of RAM broken");
> +            if (ioctl(group->fd, VFIO_GROUP_UNSET_CONTAINER,
> +                      &container->fd)) {
> +                error_report("vfio: error disconnecting group %d from"
> +                             " container", group->groupid);
> +            }
> +            return ret;
> +        }
> +        group->container = container;
> +        QLIST_INSERT_HEAD(&container->group_list, group, container_next);
> +        if (!reused) {
>              vfio_kvm_device_add_group(group);
> -            return 0;
> +            cpr_save_fd("vfio_container_for_group", group->groupid,
> +                        container->fd);
>          }
> +        return 0;
> +    }
> +
> +    if (!reused) {
> +        fd = qemu_open_old("/dev/vfio/vfio", O_RDWR);
>      }
>  
> -    fd = qemu_open_old("/dev/vfio/vfio", O_RDWR);
>      if (fd < 0) {
>          error_setg_errno(errp, errno, "failed to open /dev/vfio/vfio");
>          ret = -errno;
> @@ -2087,6 +2155,7 @@ static int vfio_connect_container(VFIOGroup *group, 
> AddressSpace *as,
>      container = g_malloc0(sizeof(*container));
>      container->space = space;
>      container->fd = fd;
> +    container->reused = reused;
>      container->error = NULL;
>      container->dirty_pages_supported = false;
>      container->dma_max_mappings = 0;
> @@ -2099,6 +2168,11 @@ static int vfio_connect_container(VFIOGroup *group, 
> AddressSpace *as,
>          goto free_container_exit;
>      }
>  
> +    ret = vfio_cpr_register_container(container, errp);
> +    if (ret) {
> +        goto free_container_exit;
> +    }
> +
>      ret = vfio_ram_block_discard_disable(container, true);
>      if (ret) {
>          error_setg_errno(errp, -ret, "Cannot set discarding of RAM broken");
> @@ -2213,9 +2287,16 @@ static int vfio_connect_container(VFIOGroup *group, 
> AddressSpace *as,
>      group->container = container;
>      QLIST_INSERT_HEAD(&container->group_list, group, container_next);
>  
> -    container->listener = vfio_memory_listener;
> -
> -    memory_listener_register(&container->listener, container->space->as);
> +    /*
> +     * If reused, register the listener later, after all state that may
> +     * affect regions and mapping boundaries has been cpr-load'ed.  Later,
> +     * the listener will invoke its callback on each flat section and call
> +     * vfio_dma_map to supply the new vaddr, and the calls will match the
> +     * mappings remembered by the kernel.
> +     */
> +    if (!reused) {
> +        vfio_listener_register(container);
> +    }
>  
>      if (container->error) {
>          ret = -1;
> @@ -2225,8 +2306,9 @@ static int vfio_connect_container(VFIOGroup *group, 
> AddressSpace *as,
>      }
>  
>      container->initialized = true;
> +    ret = cpr_resave_fd("vfio_container_for_group", group->groupid, fd, 
> errp);
>  
> -    return 0;
> +    return ret;


This needs to fall through to unwind if that resave fails.

There also needs to be vfio_cpr_unregister_container() and
cpr_delete_fd() calls in the unwind below, right?


>  listener_release_exit:
>      QLIST_REMOVE(group, container_next);
>      QLIST_REMOVE(container, next);
> @@ -2254,6 +2336,7 @@ static void vfio_disconnect_container(VFIOGroup *group)
>  
>      QLIST_REMOVE(group, container_next);
>      group->container = NULL;
> +    cpr_delete_fd("vfio_container_for_group", group->groupid);
>  
>      /*
>       * Explicitly release the listener first before unset container,
> @@ -2290,6 +2373,7 @@ static void vfio_disconnect_container(VFIOGroup *group)
>          }
>  
>          trace_vfio_disconnect_container(container->fd);
> +        vfio_cpr_unregister_container(container);
>          close(container->fd);
>          g_free(container);
>  
> @@ -2319,7 +2403,12 @@ VFIOGroup *vfio_get_group(int groupid, AddressSpace 
> *as, Error **errp)
>      group = g_malloc0(sizeof(*group));
>  
>      snprintf(path, sizeof(path), "/dev/vfio/%d", groupid);
> -    group->fd = qemu_open_old(path, O_RDWR);
> +
> +    group->fd = cpr_find_fd("vfio_group", groupid);
> +    if (group->fd < 0) {
> +        group->fd = qemu_open_old(path, O_RDWR);
> +    }
> +
>      if (group->fd < 0) {
>          error_setg_errno(errp, errno, "failed to open %s", path);
>          goto free_group_exit;
> @@ -2353,6 +2442,10 @@ VFIOGroup *vfio_get_group(int groupid, AddressSpace 
> *as, Error **errp)
>  
>      QLIST_INSERT_HEAD(&vfio_group_list, group, next);
>  
> +    if (cpr_resave_fd("vfio_group", groupid, group->fd, errp)) {
> +        goto close_fd_exit;
> +    }
> +
>      return group;
>  
>  close_fd_exit:
> @@ -2377,6 +2470,7 @@ void vfio_put_group(VFIOGroup *group)
>      vfio_disconnect_container(group);
>      QLIST_REMOVE(group, next);
>      trace_vfio_put_group(group->fd);
> +    cpr_delete_fd("vfio_group", group->groupid);
>      close(group->fd);
>      g_free(group);
>  
> @@ -2390,8 +2484,14 @@ int vfio_get_device(VFIOGroup *group, const char *name,
>  {
>      struct vfio_device_info dev_info = { .argsz = sizeof(dev_info) };
>      int ret, fd;
> +    bool reused;
> +
> +    fd = cpr_find_fd(name, 0);
> +    reused = (fd >= 0);
> +    if (!reused) {
> +        fd = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name);
> +    }
>  
> -    fd = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name);
>      if (fd < 0) {
>          error_setg_errno(errp, errno, "error getting device from group %d",
>                           group->groupid);
> @@ -2436,12 +2536,14 @@ int vfio_get_device(VFIOGroup *group, const char 
> *name,
>      vbasedev->num_irqs = dev_info.num_irqs;
>      vbasedev->num_regions = dev_info.num_regions;
>      vbasedev->flags = dev_info.flags;
> +    vbasedev->reused = reused;
>  
>      trace_vfio_get_device(name, dev_info.flags, dev_info.num_regions,
>                            dev_info.num_irqs);
>  
>      vbasedev->reset_works = !!(dev_info.flags & VFIO_DEVICE_FLAGS_RESET);
> -    return 0;
> +    ret = cpr_resave_fd(name, 0, fd, errp);
> +    return ret;


This requires new unwind code.


>  }
>  
>  void vfio_put_base_device(VFIODevice *vbasedev)
> @@ -2452,6 +2554,7 @@ void vfio_put_base_device(VFIODevice *vbasedev)
>      QLIST_REMOVE(vbasedev, next);
>      vbasedev->group = NULL;
>      trace_vfio_put_base_device(vbasedev->fd);
> +    cpr_delete_fd(vbasedev->name, 0);
>      close(vbasedev->fd);
>  }
>  
> diff --git a/hw/vfio/cpr.c b/hw/vfio/cpr.c
> new file mode 100644
> index 0000000..a227d5e
> --- /dev/null
> +++ b/hw/vfio/cpr.c
> @@ -0,0 +1,119 @@
> +/*
> + * Copyright (c) 2021, 2022 Oracle and/or its affiliates.
> + *
> + * This work is licensed under the terms of the GNU GPL, version 2.
> + * See the COPYING file in the top-level directory.
> + */
> +
> +#include "qemu/osdep.h"
> +#include <sys/ioctl.h>
> +#include <linux/vfio.h>
> +#include "hw/vfio/vfio-common.h"
> +#include "sysemu/kvm.h"
> +#include "qapi/error.h"
> +#include "migration/cpr.h"
> +#include "migration/vmstate.h"
> +#include "trace.h"
> +
> +static int
> +vfio_dma_unmap_vaddr_all(VFIOContainer *container, Error **errp)
> +{
> +    struct vfio_iommu_type1_dma_unmap unmap = {
> +        .argsz = sizeof(unmap),
> +        .flags = VFIO_DMA_UNMAP_FLAG_VADDR | VFIO_DMA_UNMAP_FLAG_ALL,
> +        .iova = 0,
> +        .size = 0,
> +    };
> +    if (ioctl(container->fd, VFIO_IOMMU_UNMAP_DMA, &unmap)) {
> +        error_setg_errno(errp, errno, "vfio_dma_unmap_vaddr_all");
> +        return -errno;
> +    }
> +    container->vaddr_unmapped = true;
> +    return 0;
> +}
> +
> +static bool vfio_is_cpr_capable(VFIOContainer *container, Error **errp)
> +{
> +    if (!ioctl(container->fd, VFIO_CHECK_EXTENSION, VFIO_UPDATE_VADDR) ||
> +        !ioctl(container->fd, VFIO_CHECK_EXTENSION, VFIO_UNMAP_ALL)) {
> +        error_setg(errp, "VFIO container does not support VFIO_UPDATE_VADDR "
> +                         "or VFIO_UNMAP_ALL");
> +        return false;
> +    } else {
> +        return true;
> +    }
> +}
> +
> +static bool vfio_vmstate_needed(void *opaque)
> +{
> +    return cpr_get_mode() == CPR_MODE_RESTART;
> +}
> +
> +static int vfio_container_pre_save(void *opaque)
> +{
> +    VFIOContainer *container = (VFIOContainer *)opaque;
> +    Error *err;
> +
> +    if (!vfio_is_cpr_capable(container, &err) ||
> +        vfio_dma_unmap_vaddr_all(container, &err)) {
> +        error_report_err(err);
> +        return -1;
> +    }
> +    return 0;
> +}
> +
> +static int vfio_container_post_load(void *opaque, int version_id)
> +{
> +    VFIOContainer *container = (VFIOContainer *)opaque;
> +    VFIOGroup *group;
> +    Error *err;
> +    VFIODevice *vbasedev;
> +
> +    if (!vfio_is_cpr_capable(container, &err)) {
> +        error_report_err(err);
> +        return -1;
> +    }
> +
> +    vfio_listener_register(container);
> +    container->reused = false;
> +
> +    QLIST_FOREACH(group, &container->group_list, container_next) {
> +        QLIST_FOREACH(vbasedev, &group->device_list, next) {
> +            vbasedev->reused = false;
> +        }
> +    }
> +    return 0;
> +}
> +
> +static const VMStateDescription vfio_container_vmstate = {
> +    .name = "vfio-container",
> +    .unmigratable = 1,


How does this work with vfio devices supporting migration?  This needs
to be coordinated with efforts to enable migration of vfio devices.


> +    .version_id = 0,
> +    .minimum_version_id = 0,
> +    .pre_save = vfio_container_pre_save,
> +    .post_load = vfio_container_post_load,
> +    .needed = vfio_vmstate_needed,


I don't see that .needed is evaluated relative to .unmigratable above
in determining if migration is blocked.


> +    .fields = (VMStateField[]) {
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +int vfio_cpr_register_container(VFIOContainer *container, Error **errp)
> +{
> +    container->cpr_blocker = NULL;
> +    if (!vfio_is_cpr_capable(container, &container->cpr_blocker)) {
> +        return cpr_add_blocker(&container->cpr_blocker, errp,
> +                               CPR_MODE_RESTART, 0);
> +    }
> +
> +    vmstate_register(NULL, -1, &vfio_container_vmstate, container);
> +
> +    return 0;
> +}
> +
> +void vfio_cpr_unregister_container(VFIOContainer *container)
> +{
> +    cpr_del_blocker(&container->cpr_blocker);
> +
> +    vmstate_unregister(NULL, &vfio_container_vmstate, container);
> +}
> diff --git a/hw/vfio/meson.build b/hw/vfio/meson.build
> index da9af29..e247b2b 100644
> --- a/hw/vfio/meson.build
> +++ b/hw/vfio/meson.build
> @@ -5,6 +5,7 @@ vfio_ss.add(files(
>    'migration.c',
>  ))
>  vfio_ss.add(when: 'CONFIG_VFIO_PCI', if_true: files(
> +  'cpr.c',
>    'display.c',
>    'pci-quirks.c',
>    'pci.c',
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index 0143c9a..237231b 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -30,6 +30,7 @@
>  #include "hw/qdev-properties-system.h"
>  #include "migration/vmstate.h"
>  #include "qapi/qmp/qdict.h"
> +#include "migration/cpr.h"
>  #include "qemu/error-report.h"
>  #include "qemu/main-loop.h"
>  #include "qemu/module.h"
> @@ -2514,6 +2515,7 @@ const VMStateDescription vmstate_vfio_pci_config = {
>      .name = "VFIOPCIDevice",
>      .version_id = 1,
>      .minimum_version_id = 1,
> +    .priority = MIG_PRI_VFIO_PCI,   /* * must load before container */
>      .fields = (VMStateField[]) {
>          VMSTATE_PCI_DEVICE(pdev, VFIOPCIDevice),
>          VMSTATE_MSIX_TEST(pdev, VFIOPCIDevice, vfio_msix_present),
> @@ -3243,6 +3245,11 @@ static void vfio_pci_reset(DeviceState *dev)
>  {
>      VFIOPCIDevice *vdev = VFIO_PCI(dev);
>  
> +    /* Do not reset the device during qemu_system_reset prior to cpr-load */
> +    if (vdev->vbasedev.reused) {
> +        return;
> +    }
> +
>      trace_vfio_pci_reset(vdev->vbasedev.name);
>  
>      vfio_pci_pre_reset(vdev);
> @@ -3350,6 +3357,42 @@ static Property vfio_pci_dev_properties[] = {
>      DEFINE_PROP_END_OF_LIST(),
>  };
>  
> +/*
> + * The kernel may change non-emulated config bits.  Exclude them from the
> + * changed-bits check in get_pci_config_device.
> + */
> +static int vfio_pci_pre_load(void *opaque)
> +{
> +    VFIOPCIDevice *vdev = opaque;
> +    PCIDevice *pdev = &vdev->pdev;
> +    int size = MIN(pci_config_size(pdev), vdev->config_size);
> +    int i;
> +
> +    for (i = 0; i < size; i++) {
> +        pdev->cmask[i] &= vdev->emulated_config_bits[i];
> +    }
> +
> +    return 0;
> +}
> +
> +static bool vfio_pci_needed(void *opaque)
> +{
> +    return cpr_get_mode() == CPR_MODE_RESTART;
> +}
> +
> +static const VMStateDescription vfio_pci_vmstate = {
> +    .name = "vfio-pci",
> +    .unmigratable = 1,


Same question here.


> +    .version_id = 0,
> +    .minimum_version_id = 0,
> +    .priority = MIG_PRI_VFIO_PCI,       /* must load before container */
> +    .pre_load = vfio_pci_pre_load,
> +    .needed = vfio_pci_needed,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
>  static void vfio_pci_dev_class_init(ObjectClass *klass, void *data)
>  {
>      DeviceClass *dc = DEVICE_CLASS(klass);
> @@ -3357,6 +3400,7 @@ static void vfio_pci_dev_class_init(ObjectClass *klass, 
> void *data)
>  
>      dc->reset = vfio_pci_reset;
>      device_class_set_props(dc, vfio_pci_dev_properties);
> +    dc->vmsd = &vfio_pci_vmstate;
>      dc->desc = "VFIO-based PCI device assignment";
>      set_bit(DEVICE_CATEGORY_MISC, dc->categories);
>      pdc->realize = vfio_realize;
> diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events
> index 73dffe9..a6d0034 100644
> --- a/hw/vfio/trace-events
> +++ b/hw/vfio/trace-events
> @@ -119,6 +119,7 @@ vfio_region_sparse_mmap_header(const char *name, int 
> index, int nr_areas) "Devic
>  vfio_region_sparse_mmap_entry(int i, unsigned long start, unsigned long end) 
> "sparse entry %d [0x%lx - 0x%lx]"
>  vfio_get_dev_region(const char *name, int index, uint32_t type, uint32_t 
> subtype) "%s index %d, %08x/%0x8"
>  vfio_dma_unmap_overflow_workaround(void) ""
> +vfio_region_remap(const char *name, int fd, uint64_t iova_start, uint64_t 
> iova_end, void *vaddr) "%s fd %d 0x%"PRIx64" - 0x%"PRIx64" [%p]"
>  
>  # platform.c
>  vfio_platform_base_device_init(char *name, int groupid) "%s belongs to group 
> #%d"
> diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
> index e573f5a..17ad9ba 100644
> --- a/include/hw/vfio/vfio-common.h
> +++ b/include/hw/vfio/vfio-common.h
> @@ -81,10 +81,14 @@ typedef struct VFIOContainer {
>      int fd; /* /dev/vfio/vfio, empowered by the attached groups */
>      MemoryListener listener;
>      MemoryListener prereg_listener;
> +    Notifier cpr_notifier;
> +    Error *cpr_blocker;
>      unsigned iommu_type;
>      Error *error;
>      bool initialized;
>      bool dirty_pages_supported;
> +    bool reused;
> +    bool vaddr_unmapped;
>      uint64_t dirty_pgsizes;
>      uint64_t max_dirty_bitmap_size;
>      unsigned long pgsizes;
> @@ -136,6 +140,7 @@ typedef struct VFIODevice {
>      bool no_mmap;
>      bool ram_block_discard_allowed;
>      bool enable_migration;
> +    bool reused;
>      VFIODeviceOps *ops;
>      unsigned int num_irqs;
>      unsigned int num_regions;
> @@ -213,6 +218,9 @@ void vfio_put_group(VFIOGroup *group);
>  int vfio_get_device(VFIOGroup *group, const char *name,
>                      VFIODevice *vbasedev, Error **errp);
>  
> +int vfio_cpr_register_container(VFIOContainer *container, Error **errp);
> +void vfio_cpr_unregister_container(VFIOContainer *container);
> +
>  extern const MemoryRegionOps vfio_region_ops;
>  typedef QLIST_HEAD(VFIOGroupList, VFIOGroup) VFIOGroupList;
>  extern VFIOGroupList vfio_group_list;
> @@ -234,6 +242,9 @@ struct vfio_info_cap_header *
>  vfio_get_device_info_cap(struct vfio_device_info *info, uint16_t id);
>  #endif
>  extern const MemoryListener vfio_prereg_listener;
> +void vfio_listener_register(VFIOContainer *container);
> +void vfio_container_region_add(VFIOContainer *container,
> +                               MemoryRegionSection *section);
>  
>  int vfio_spapr_create_window(VFIOContainer *container,
>                               MemoryRegionSection *section,
> diff --git a/include/migration/vmstate.h b/include/migration/vmstate.h
> index ad24aa1..19f1538 100644
> --- a/include/migration/vmstate.h
> +++ b/include/migration/vmstate.h
> @@ -157,6 +157,7 @@ typedef enum {
>      MIG_PRI_GICV3_ITS,          /* Must happen before PCI devices */
>      MIG_PRI_GICV3,              /* Must happen before the ITS */
>      MIG_PRI_MAX,
> +    MIG_PRI_VFIO_PCI = MIG_PRI_IOMMU,


Based on the current contents of this enum, why are we aliasing a
existing priority vs defining a new one?  Thanks,

Alex


>  } MigrationPriority;
>  
>  struct VMStateField {




reply via email to

[Prev in Thread] Current Thread [Next in Thread]