diff mbox

[v4,08/10] vfio: vote the function 0 to do host bus reset when aer occurred

Message ID 1458554926-7844-9-git-send-email-caoj.fnst@cn.fujitsu.com (mailing list archive)
State New, archived
Headers show

Commit Message

Cao jin March 21, 2016, 10:08 a.m. UTC
From: Chen Fan <chen.fan.fnst@cn.fujitsu.com>

Due to all devices assigned to VM on the same way as host if enable
aer, so we can easily do the hot reset by selecting the function #0
to do the hot reset.

Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
---
 hw/vfio/pci.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
 hw/vfio/pci.h |  2 ++
 2 files changed, 52 insertions(+)

Comments

Alex Williamson March 21, 2016, 9:40 p.m. UTC | #1
On Mon, 21 Mar 2016 18:08:44 +0800
Cao jin <caoj.fnst@cn.fujitsu.com> wrote:

> From: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
> 
> Due to all devices assigned to VM on the same way as host if enable
> aer, so we can easily do the hot reset by selecting the function #0
> to do the hot reset.
> 
> Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
> ---
>  hw/vfio/pci.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
>  hw/vfio/pci.h |  2 ++
>  2 files changed, 52 insertions(+)
> 
> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> index 9902c87..718cde7 100644
> --- a/hw/vfio/pci.c
> +++ b/hw/vfio/pci.c
> @@ -1900,6 +1900,8 @@ static void vfio_check_hot_bus_reset(VFIOPCIDevice *vdev, Error **errp)
>      /* List all affected devices by bus reset */
>      devices = &info->devices[0];
>  
> +    vdev->single_depend_dev = (info->count == 1);
> +
>      /* Verify that we have all the groups required */
>      for (i = 0; i < info->count; i++) {
>          PCIHostDeviceAddress host;
> @@ -2608,11 +2610,36 @@ static void vfio_put_device(VFIOPCIDevice *vdev)
>  static void vfio_err_notifier_handler(void *opaque)
>  {
>      VFIOPCIDevice *vdev = opaque;
> +    PCIDevice *pdev = &vdev->pdev;
>  
>      if (!event_notifier_test_and_clear(&vdev->err_notifier)) {
>          return;
>      }
>  
> +    if (vdev->features & VFIO_FEATURE_ENABLE_AER) {
> +        VFIOPCIDevice *tmp;
> +        PCIDevice *dev;
> +        int devfn;
> +
> +        /*
> +         * If one device has aer capability on a bus, when aer occurred,
> +         * we should notify all devices on the bus there was an aer arrived,
> +         * then we are able to vote the device #0 to do host bus reset.
> +         */
> +        for (devfn = 0; devfn < 8; devfn++) {

ARI?

> +            dev = pci_find_device(pdev->bus, pci_bus_num(pdev->bus),
> +                      PCI_DEVFN(PCI_SLOT(pdev->devfn), devfn));
> +            if (!dev) {
> +                continue;
> +            }
> +            if (!object_dynamic_cast(OBJECT(dev), "vfio-pci")) {
> +                continue;
> +            }
> +            tmp = DO_UPCAST(VFIOPCIDevice, pdev, dev);
> +            tmp->aer_occurred = true;
> +        }
> +    }
> +
>      /*
>       * TBD. Retrieve the error details and decide what action
>       * needs to be taken. One of the actions could be to pass
> @@ -3075,6 +3102,29 @@ static void vfio_pci_reset(DeviceState *dev)
>  
>      trace_vfio_pci_reset(vdev->vbasedev.name);
>  
> +    if (vdev->aer_occurred) {
> +        PCIDevice *br = pci_bridge_get_device(pdev->bus);
> +
> +        if (br &&
> +            (pci_get_word(br->config + PCI_BRIDGE_CONTROL) &
> +             PCI_BRIDGE_CTL_BUS_RESET)) {
> +            /* simply voting the function 0 to do hot bus reset */
> +            if (pci_get_function_0(pdev) == pdev) {
> +                if (vdev->features & VFIO_FEATURE_ENABLE_AER) {
> +                    vfio_pci_hot_reset(vdev, vdev->single_depend_dev);
> +                } else {
> +                    /* if this device has not AER capability, code
> +                     * coming here indicates there is another function
> +                     * on the bus has AER capability.
> +                     * */

This shouldn't be possible, right?

> +                    vfio_pci_hot_reset(vdev, false);
> +                }
> +            }
> +            vdev->aer_occurred = false;
> +            return;
> +        }
> +    }

Why do we care than an AER occurred now?  Can't we simply test:

    if (vdev->features & VFIO_FEATURE_ENABLE_AER &&
        pci_get_function_0(pdev) == pdev) {
        PCIDevice *br = pci_bridge_get_device(pdev->bus);

        if (pci_get_word(br->config + PCI_BRIDGE_CONTROL) &
            PCI_BRIDGE_CTL_BUS_RESET)) {

            vfio_pci_hot_reset(vdev, vdev->single_depend_dev);
            return;
        }
    }

> +
>      vfio_pci_pre_reset(vdev);
>  
>      if (vdev->resetfn && !vdev->resetfn(vdev)) {
> diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
> index db7c6d5..17c75b8 100644
> --- a/hw/vfio/pci.h
> +++ b/hw/vfio/pci.h
> @@ -143,6 +143,8 @@ typedef struct VFIOPCIDevice {
>      bool no_kvm_intx;
>      bool no_kvm_msi;
>      bool no_kvm_msix;
> +    bool aer_occurred;
> +    bool single_depend_dev;
>  } VFIOPCIDevice;
>  
>  uint32_t vfio_pci_read_config(PCIDevice *pdev, uint32_t addr, int len);
Chen Fan March 22, 2016, 10:14 a.m. UTC | #2
On 03/22/2016 05:40 AM, Alex Williamson wrote:
> On Mon, 21 Mar 2016 18:08:44 +0800
> Cao jin <caoj.fnst@cn.fujitsu.com> wrote:
>
>> From: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
>>
>> Due to all devices assigned to VM on the same way as host if enable
>> aer, so we can easily do the hot reset by selecting the function #0
>> to do the hot reset.
>>
>> Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
>> ---
>>   hw/vfio/pci.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
>>   hw/vfio/pci.h |  2 ++
>>   2 files changed, 52 insertions(+)
>>
>> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
>> index 9902c87..718cde7 100644
>> --- a/hw/vfio/pci.c
>> +++ b/hw/vfio/pci.c
>> @@ -1900,6 +1900,8 @@ static void vfio_check_hot_bus_reset(VFIOPCIDevice *vdev, Error **errp)
>>       /* List all affected devices by bus reset */
>>       devices = &info->devices[0];
>>   
>> +    vdev->single_depend_dev = (info->count == 1);
>> +
>>       /* Verify that we have all the groups required */
>>       for (i = 0; i < info->count; i++) {
>>           PCIHostDeviceAddress host;
>> @@ -2608,11 +2610,36 @@ static void vfio_put_device(VFIOPCIDevice *vdev)
>>   static void vfio_err_notifier_handler(void *opaque)
>>   {
>>       VFIOPCIDevice *vdev = opaque;
>> +    PCIDevice *pdev = &vdev->pdev;
>>   
>>       if (!event_notifier_test_and_clear(&vdev->err_notifier)) {
>>           return;
>>       }
>>   
>> +    if (vdev->features & VFIO_FEATURE_ENABLE_AER) {
>> +        VFIOPCIDevice *tmp;
>> +        PCIDevice *dev;
>> +        int devfn;
>> +
>> +        /*
>> +         * If one device has aer capability on a bus, when aer occurred,
>> +         * we should notify all devices on the bus there was an aer arrived,
>> +         * then we are able to vote the device #0 to do host bus reset.
>> +         */
>> +        for (devfn = 0; devfn < 8; devfn++) {
> ARI?
>
>> +            dev = pci_find_device(pdev->bus, pci_bus_num(pdev->bus),
>> +                      PCI_DEVFN(PCI_SLOT(pdev->devfn), devfn));
>> +            if (!dev) {
>> +                continue;
>> +            }
>> +            if (!object_dynamic_cast(OBJECT(dev), "vfio-pci")) {
>> +                continue;
>> +            }
>> +            tmp = DO_UPCAST(VFIOPCIDevice, pdev, dev);
>> +            tmp->aer_occurred = true;
>> +        }
>> +    }
>> +
>>       /*
>>        * TBD. Retrieve the error details and decide what action
>>        * needs to be taken. One of the actions could be to pass
>> @@ -3075,6 +3102,29 @@ static void vfio_pci_reset(DeviceState *dev)
>>   
>>       trace_vfio_pci_reset(vdev->vbasedev.name);
>>   
>> +    if (vdev->aer_occurred) {
>> +        PCIDevice *br = pci_bridge_get_device(pdev->bus);
>> +
>> +        if (br &&
>> +            (pci_get_word(br->config + PCI_BRIDGE_CONTROL) &
>> +             PCI_BRIDGE_CTL_BUS_RESET)) {
>> +            /* simply voting the function 0 to do hot bus reset */
>> +            if (pci_get_function_0(pdev) == pdev) {
>> +                if (vdev->features & VFIO_FEATURE_ENABLE_AER) {
>> +                    vfio_pci_hot_reset(vdev, vdev->single_depend_dev);
>> +                } else {
>> +                    /* if this device has not AER capability, code
>> +                     * coming here indicates there is another function
>> +                     * on the bus has AER capability.
>> +                     * */
> This shouldn't be possible, right?
>
>> +                    vfio_pci_hot_reset(vdev, false);
>> +                }
>> +            }
>> +            vdev->aer_occurred = false;
>> +            return;
>> +        }
>> +    }
> Why do we care than an AER occurred now?  Can't we simply test:
>
>      if (vdev->features & VFIO_FEATURE_ENABLE_AER &&
>          pci_get_function_0(pdev) == pdev) {
>          PCIDevice *br = pci_bridge_get_device(pdev->bus);
>
>          if (pci_get_word(br->config + PCI_BRIDGE_CONTROL) &
>              PCI_BRIDGE_CTL_BUS_RESET)) {
>
>              vfio_pci_hot_reset(vdev, vdev->single_depend_dev);
>              return;
>          }
>      }

do we have the case that only one/few of the devices affected
by a bus reset assigned to VM enabled AER, then when bus
reset, we let the function 0 do hot reset, which may not enable AER,
but we should tell other devices on the bus that they don't need
to do bus reset. so I just mark all devices on the bus when needing a 
hot reset.

Thanks,
Chen



>
>> +
>>       vfio_pci_pre_reset(vdev);
>>   
>>       if (vdev->resetfn && !vdev->resetfn(vdev)) {
>> diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
>> index db7c6d5..17c75b8 100644
>> --- a/hw/vfio/pci.h
>> +++ b/hw/vfio/pci.h
>> @@ -143,6 +143,8 @@ typedef struct VFIOPCIDevice {
>>       bool no_kvm_intx;
>>       bool no_kvm_msi;
>>       bool no_kvm_msix;
>> +    bool aer_occurred;
>> +    bool single_depend_dev;
>>   } VFIOPCIDevice;
>>   
>>   uint32_t vfio_pci_read_config(PCIDevice *pdev, uint32_t addr, int len);
>
>
> .
>
Alex Williamson March 22, 2016, 4:07 p.m. UTC | #3
On Tue, 22 Mar 2016 18:14:45 +0800
Chen Fan <chen.fan.fnst@cn.fujitsu.com> wrote:

> On 03/22/2016 05:40 AM, Alex Williamson wrote:
> > On Mon, 21 Mar 2016 18:08:44 +0800
> > Cao jin <caoj.fnst@cn.fujitsu.com> wrote:
> >  
> >> From: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
> >>
> >> Due to all devices assigned to VM on the same way as host if enable
> >> aer, so we can easily do the hot reset by selecting the function #0
> >> to do the hot reset.
> >>
> >> Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
> >> ---
> >>   hw/vfio/pci.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
> >>   hw/vfio/pci.h |  2 ++
> >>   2 files changed, 52 insertions(+)
> >>
> >> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
> >> index 9902c87..718cde7 100644
> >> --- a/hw/vfio/pci.c
> >> +++ b/hw/vfio/pci.c
> >> @@ -1900,6 +1900,8 @@ static void vfio_check_hot_bus_reset(VFIOPCIDevice *vdev, Error **errp)
> >>       /* List all affected devices by bus reset */
> >>       devices = &info->devices[0];
> >>   
> >> +    vdev->single_depend_dev = (info->count == 1);
> >> +
> >>       /* Verify that we have all the groups required */
> >>       for (i = 0; i < info->count; i++) {
> >>           PCIHostDeviceAddress host;
> >> @@ -2608,11 +2610,36 @@ static void vfio_put_device(VFIOPCIDevice *vdev)
> >>   static void vfio_err_notifier_handler(void *opaque)
> >>   {
> >>       VFIOPCIDevice *vdev = opaque;
> >> +    PCIDevice *pdev = &vdev->pdev;
> >>   
> >>       if (!event_notifier_test_and_clear(&vdev->err_notifier)) {
> >>           return;
> >>       }
> >>   
> >> +    if (vdev->features & VFIO_FEATURE_ENABLE_AER) {
> >> +        VFIOPCIDevice *tmp;
> >> +        PCIDevice *dev;
> >> +        int devfn;
> >> +
> >> +        /*
> >> +         * If one device has aer capability on a bus, when aer occurred,
> >> +         * we should notify all devices on the bus there was an aer arrived,
> >> +         * then we are able to vote the device #0 to do host bus reset.
> >> +         */
> >> +        for (devfn = 0; devfn < 8; devfn++) {  
> > ARI?
> >  
> >> +            dev = pci_find_device(pdev->bus, pci_bus_num(pdev->bus),
> >> +                      PCI_DEVFN(PCI_SLOT(pdev->devfn), devfn));
> >> +            if (!dev) {
> >> +                continue;
> >> +            }
> >> +            if (!object_dynamic_cast(OBJECT(dev), "vfio-pci")) {
> >> +                continue;
> >> +            }
> >> +            tmp = DO_UPCAST(VFIOPCIDevice, pdev, dev);
> >> +            tmp->aer_occurred = true;
> >> +        }
> >> +    }
> >> +
> >>       /*
> >>        * TBD. Retrieve the error details and decide what action
> >>        * needs to be taken. One of the actions could be to pass
> >> @@ -3075,6 +3102,29 @@ static void vfio_pci_reset(DeviceState *dev)
> >>   
> >>       trace_vfio_pci_reset(vdev->vbasedev.name);
> >>   
> >> +    if (vdev->aer_occurred) {
> >> +        PCIDevice *br = pci_bridge_get_device(pdev->bus);
> >> +
> >> +        if (br &&
> >> +            (pci_get_word(br->config + PCI_BRIDGE_CONTROL) &
> >> +             PCI_BRIDGE_CTL_BUS_RESET)) {
> >> +            /* simply voting the function 0 to do hot bus reset */
> >> +            if (pci_get_function_0(pdev) == pdev) {
> >> +                if (vdev->features & VFIO_FEATURE_ENABLE_AER) {
> >> +                    vfio_pci_hot_reset(vdev, vdev->single_depend_dev);
> >> +                } else {
> >> +                    /* if this device has not AER capability, code
> >> +                     * coming here indicates there is another function
> >> +                     * on the bus has AER capability.
> >> +                     * */  
> > This shouldn't be possible, right?
> >  
> >> +                    vfio_pci_hot_reset(vdev, false);
> >> +                }
> >> +            }
> >> +            vdev->aer_occurred = false;
> >> +            return;
> >> +        }
> >> +    }  
> > Why do we care than an AER occurred now?  Can't we simply test:
> >
> >      if (vdev->features & VFIO_FEATURE_ENABLE_AER &&
> >          pci_get_function_0(pdev) == pdev) {
> >          PCIDevice *br = pci_bridge_get_device(pdev->bus);
> >
> >          if (pci_get_word(br->config + PCI_BRIDGE_CONTROL) &
> >              PCI_BRIDGE_CTL_BUS_RESET)) {
> >
> >              vfio_pci_hot_reset(vdev, vdev->single_depend_dev);
> >              return;
> >          }
> >      }  
> 
> do we have the case that only one/few of the devices affected
> by a bus reset assigned to VM enabled AER, then when bus
> reset, we let the function 0 do hot reset, which may not enable AER,
> but we should tell other devices on the bus that they don't need
> to do bus reset. so I just mark all devices on the bus when needing a 
> hot reset.

I thought we were requiring all the bus reset affected devices to
enable AER, so that example should not be possible.  I think it matches
our target use case to make this a requirement.  Thanks,

Alex
Chen Fan March 23, 2016, 6:25 a.m. UTC | #4
On 03/22/2016 05:40 AM, Alex Williamson wrote:
> On Mon, 21 Mar 2016 18:08:44 +0800
> Cao jin <caoj.fnst@cn.fujitsu.com> wrote:
>
>> From: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
>>
>> Due to all devices assigned to VM on the same way as host if enable
>> aer, so we can easily do the hot reset by selecting the function #0
>> to do the hot reset.
>>
>> Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
>> ---
>>   hw/vfio/pci.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
>>   hw/vfio/pci.h |  2 ++
>>   2 files changed, 52 insertions(+)
>>
>> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
>> index 9902c87..718cde7 100644
>> --- a/hw/vfio/pci.c
>> +++ b/hw/vfio/pci.c
>> @@ -1900,6 +1900,8 @@ static void vfio_check_hot_bus_reset(VFIOPCIDevice *vdev, Error **errp)
>>       /* List all affected devices by bus reset */
>>       devices = &info->devices[0];
>>   
>> +    vdev->single_depend_dev = (info->count == 1);
>> +
>>       /* Verify that we have all the groups required */
>>       for (i = 0; i < info->count; i++) {
>>           PCIHostDeviceAddress host;
>> @@ -2608,11 +2610,36 @@ static void vfio_put_device(VFIOPCIDevice *vdev)
>>   static void vfio_err_notifier_handler(void *opaque)
>>   {
>>       VFIOPCIDevice *vdev = opaque;
>> +    PCIDevice *pdev = &vdev->pdev;
>>   
>>       if (!event_notifier_test_and_clear(&vdev->err_notifier)) {
>>           return;
>>       }
>>   
>> +    if (vdev->features & VFIO_FEATURE_ENABLE_AER) {
>> +        VFIOPCIDevice *tmp;
>> +        PCIDevice *dev;
>> +        int devfn;
>> +
>> +        /*
>> +         * If one device has aer capability on a bus, when aer occurred,
>> +         * we should notify all devices on the bus there was an aer arrived,
>> +         * then we are able to vote the device #0 to do host bus reset.
>> +         */
>> +        for (devfn = 0; devfn < 8; devfn++) {
> ARI?
>
>> +            dev = pci_find_device(pdev->bus, pci_bus_num(pdev->bus),
>> +                      PCI_DEVFN(PCI_SLOT(pdev->devfn), devfn));
>> +            if (!dev) {
>> +                continue;
>> +            }
>> +            if (!object_dynamic_cast(OBJECT(dev), "vfio-pci")) {
>> +                continue;
>> +            }
>> +            tmp = DO_UPCAST(VFIOPCIDevice, pdev, dev);
>> +            tmp->aer_occurred = true;
>> +        }
>> +    }
>> +
>>       /*
>>        * TBD. Retrieve the error details and decide what action
>>        * needs to be taken. One of the actions could be to pass
>> @@ -3075,6 +3102,29 @@ static void vfio_pci_reset(DeviceState *dev)
>>   
>>       trace_vfio_pci_reset(vdev->vbasedev.name);
>>   
>> +    if (vdev->aer_occurred) {
>> +        PCIDevice *br = pci_bridge_get_device(pdev->bus);
>> +
>> +        if (br &&
>> +            (pci_get_word(br->config + PCI_BRIDGE_CONTROL) &
>> +             PCI_BRIDGE_CTL_BUS_RESET)) {
>> +            /* simply voting the function 0 to do hot bus reset */
>> +            if (pci_get_function_0(pdev) == pdev) {
>> +                if (vdev->features & VFIO_FEATURE_ENABLE_AER) {
>> +                    vfio_pci_hot_reset(vdev, vdev->single_depend_dev);
>> +                } else {
>> +                    /* if this device has not AER capability, code
>> +                     * coming here indicates there is another function
>> +                     * on the bus has AER capability.
>> +                     * */
> This shouldn't be possible, right?
>
>> +                    vfio_pci_hot_reset(vdev, false);
>> +                }
>> +            }
>> +            vdev->aer_occurred = false;
>> +            return;
>> +        }
>> +    }
> Why do we care than an AER occurred now?  Can't we simply test:
>
>      if (vdev->features & VFIO_FEATURE_ENABLE_AER &&
>          pci_get_function_0(pdev) == pdev) {
>          PCIDevice *br = pci_bridge_get_device(pdev->bus);
>
>          if (pci_get_word(br->config + PCI_BRIDGE_CONTROL) &
>              PCI_BRIDGE_CTL_BUS_RESET)) {
>
>              vfio_pci_hot_reset(vdev, vdev->single_depend_dev);
>              return;
>          }
>      }
I think this is not practicable, not_function_0 device can't
pass the condition, it would do reset normally. but our intention
is doing nothing for them, and direct return.
I will change this in next version.

Thanks,
CHen

>
>> +
>>       vfio_pci_pre_reset(vdev);
>>   
>>       if (vdev->resetfn && !vdev->resetfn(vdev)) {
>> diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
>> index db7c6d5..17c75b8 100644
>> --- a/hw/vfio/pci.h
>> +++ b/hw/vfio/pci.h
>> @@ -143,6 +143,8 @@ typedef struct VFIOPCIDevice {
>>       bool no_kvm_intx;
>>       bool no_kvm_msi;
>>       bool no_kvm_msix;
>> +    bool aer_occurred;
>> +    bool single_depend_dev;
>>   } VFIOPCIDevice;
>>   
>>   uint32_t vfio_pci_read_config(PCIDevice *pdev, uint32_t addr, int len);
>
>
> .
>
Chen Fan March 23, 2016, 6:25 a.m. UTC | #5
On 03/22/2016 05:40 AM, Alex Williamson wrote:
> On Mon, 21 Mar 2016 18:08:44 +0800
> Cao jin <caoj.fnst@cn.fujitsu.com> wrote:
>
>> From: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
>>
>> Due to all devices assigned to VM on the same way as host if enable
>> aer, so we can easily do the hot reset by selecting the function #0
>> to do the hot reset.
>>
>> Signed-off-by: Chen Fan <chen.fan.fnst@cn.fujitsu.com>
>> ---
>>   hw/vfio/pci.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
>>   hw/vfio/pci.h |  2 ++
>>   2 files changed, 52 insertions(+)
>>
>> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
>> index 9902c87..718cde7 100644
>> --- a/hw/vfio/pci.c
>> +++ b/hw/vfio/pci.c
>> @@ -1900,6 +1900,8 @@ static void vfio_check_hot_bus_reset(VFIOPCIDevice *vdev, Error **errp)
>>       /* List all affected devices by bus reset */
>>       devices = &info->devices[0];
>>   
>> +    vdev->single_depend_dev = (info->count == 1);
>> +
>>       /* Verify that we have all the groups required */
>>       for (i = 0; i < info->count; i++) {
>>           PCIHostDeviceAddress host;
>> @@ -2608,11 +2610,36 @@ static void vfio_put_device(VFIOPCIDevice *vdev)
>>   static void vfio_err_notifier_handler(void *opaque)
>>   {
>>       VFIOPCIDevice *vdev = opaque;
>> +    PCIDevice *pdev = &vdev->pdev;
>>   
>>       if (!event_notifier_test_and_clear(&vdev->err_notifier)) {
>>           return;
>>       }
>>   
>> +    if (vdev->features & VFIO_FEATURE_ENABLE_AER) {
>> +        VFIOPCIDevice *tmp;
>> +        PCIDevice *dev;
>> +        int devfn;
>> +
>> +        /*
>> +         * If one device has aer capability on a bus, when aer occurred,
>> +         * we should notify all devices on the bus there was an aer arrived,
>> +         * then we are able to vote the device #0 to do host bus reset.
>> +         */
>> +        for (devfn = 0; devfn < 8; devfn++) {
> ARI?
>
>> +            dev = pci_find_device(pdev->bus, pci_bus_num(pdev->bus),
>> +                      PCI_DEVFN(PCI_SLOT(pdev->devfn), devfn));
>> +            if (!dev) {
>> +                continue;
>> +            }
>> +            if (!object_dynamic_cast(OBJECT(dev), "vfio-pci")) {
>> +                continue;
>> +            }
>> +            tmp = DO_UPCAST(VFIOPCIDevice, pdev, dev);
>> +            tmp->aer_occurred = true;
>> +        }
>> +    }
>> +
>>       /*
>>        * TBD. Retrieve the error details and decide what action
>>        * needs to be taken. One of the actions could be to pass
>> @@ -3075,6 +3102,29 @@ static void vfio_pci_reset(DeviceState *dev)
>>   
>>       trace_vfio_pci_reset(vdev->vbasedev.name);
>>   
>> +    if (vdev->aer_occurred) {
>> +        PCIDevice *br = pci_bridge_get_device(pdev->bus);
>> +
>> +        if (br &&
>> +            (pci_get_word(br->config + PCI_BRIDGE_CONTROL) &
>> +             PCI_BRIDGE_CTL_BUS_RESET)) {
>> +            /* simply voting the function 0 to do hot bus reset */
>> +            if (pci_get_function_0(pdev) == pdev) {
>> +                if (vdev->features & VFIO_FEATURE_ENABLE_AER) {
>> +                    vfio_pci_hot_reset(vdev, vdev->single_depend_dev);
>> +                } else {
>> +                    /* if this device has not AER capability, code
>> +                     * coming here indicates there is another function
>> +                     * on the bus has AER capability.
>> +                     * */
> This shouldn't be possible, right?
>
>> +                    vfio_pci_hot_reset(vdev, false);
>> +                }
>> +            }
>> +            vdev->aer_occurred = false;
>> +            return;
>> +        }
>> +    }
> Why do we care than an AER occurred now?  Can't we simply test:
>
>      if (vdev->features & VFIO_FEATURE_ENABLE_AER &&
>          pci_get_function_0(pdev) == pdev) {
>          PCIDevice *br = pci_bridge_get_device(pdev->bus);
>
>          if (pci_get_word(br->config + PCI_BRIDGE_CONTROL) &
>              PCI_BRIDGE_CTL_BUS_RESET)) {
>
>              vfio_pci_hot_reset(vdev, vdev->single_depend_dev);
>              return;
>          }
>      }
I think this is not practicable, not_function_0 device can't
pass the condition, it would do reset normally. but our intention
is doing nothing for them, and direct return.
I will change this in next version.

Thanks,
Chen

>
>> +
>>       vfio_pci_pre_reset(vdev);
>>   
>>       if (vdev->resetfn && !vdev->resetfn(vdev)) {
>> diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
>> index db7c6d5..17c75b8 100644
>> --- a/hw/vfio/pci.h
>> +++ b/hw/vfio/pci.h
>> @@ -143,6 +143,8 @@ typedef struct VFIOPCIDevice {
>>       bool no_kvm_intx;
>>       bool no_kvm_msi;
>>       bool no_kvm_msix;
>> +    bool aer_occurred;
>> +    bool single_depend_dev;
>>   } VFIOPCIDevice;
>>   
>>   uint32_t vfio_pci_read_config(PCIDevice *pdev, uint32_t addr, int len);
>
>
> .
>
diff mbox

Patch

diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 9902c87..718cde7 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -1900,6 +1900,8 @@  static void vfio_check_hot_bus_reset(VFIOPCIDevice *vdev, Error **errp)
     /* List all affected devices by bus reset */
     devices = &info->devices[0];
 
+    vdev->single_depend_dev = (info->count == 1);
+
     /* Verify that we have all the groups required */
     for (i = 0; i < info->count; i++) {
         PCIHostDeviceAddress host;
@@ -2608,11 +2610,36 @@  static void vfio_put_device(VFIOPCIDevice *vdev)
 static void vfio_err_notifier_handler(void *opaque)
 {
     VFIOPCIDevice *vdev = opaque;
+    PCIDevice *pdev = &vdev->pdev;
 
     if (!event_notifier_test_and_clear(&vdev->err_notifier)) {
         return;
     }
 
+    if (vdev->features & VFIO_FEATURE_ENABLE_AER) {
+        VFIOPCIDevice *tmp;
+        PCIDevice *dev;
+        int devfn;
+
+        /*
+         * If one device has aer capability on a bus, when aer occurred,
+         * we should notify all devices on the bus there was an aer arrived,
+         * then we are able to vote the device #0 to do host bus reset.
+         */
+        for (devfn = 0; devfn < 8; devfn++) {
+            dev = pci_find_device(pdev->bus, pci_bus_num(pdev->bus),
+                      PCI_DEVFN(PCI_SLOT(pdev->devfn), devfn));
+            if (!dev) {
+                continue;
+            }
+            if (!object_dynamic_cast(OBJECT(dev), "vfio-pci")) {
+                continue;
+            }
+            tmp = DO_UPCAST(VFIOPCIDevice, pdev, dev);
+            tmp->aer_occurred = true;
+        }
+    }
+
     /*
      * TBD. Retrieve the error details and decide what action
      * needs to be taken. One of the actions could be to pass
@@ -3075,6 +3102,29 @@  static void vfio_pci_reset(DeviceState *dev)
 
     trace_vfio_pci_reset(vdev->vbasedev.name);
 
+    if (vdev->aer_occurred) {
+        PCIDevice *br = pci_bridge_get_device(pdev->bus);
+
+        if (br &&
+            (pci_get_word(br->config + PCI_BRIDGE_CONTROL) &
+             PCI_BRIDGE_CTL_BUS_RESET)) {
+            /* simply voting the function 0 to do hot bus reset */
+            if (pci_get_function_0(pdev) == pdev) {
+                if (vdev->features & VFIO_FEATURE_ENABLE_AER) {
+                    vfio_pci_hot_reset(vdev, vdev->single_depend_dev);
+                } else {
+                    /* if this device has not AER capability, code
+                     * coming here indicates there is another function
+                     * on the bus has AER capability.
+                     * */
+                    vfio_pci_hot_reset(vdev, false);
+                }
+            }
+            vdev->aer_occurred = false;
+            return;
+        }
+    }
+
     vfio_pci_pre_reset(vdev);
 
     if (vdev->resetfn && !vdev->resetfn(vdev)) {
diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
index db7c6d5..17c75b8 100644
--- a/hw/vfio/pci.h
+++ b/hw/vfio/pci.h
@@ -143,6 +143,8 @@  typedef struct VFIOPCIDevice {
     bool no_kvm_intx;
     bool no_kvm_msi;
     bool no_kvm_msix;
+    bool aer_occurred;
+    bool single_depend_dev;
 } VFIOPCIDevice;
 
 uint32_t vfio_pci_read_config(PCIDevice *pdev, uint32_t addr, int len);