Re: [Qemu-devel] [PATCH v6 08/16] hw/vfio: create common module

[Alexander Graf <agraf@suse.de>]

On 11.09.14 14:11, Eric Auger wrote:
> On 09/10/2014 03:09 PM, Alexander Graf wrote:
>>
>>
>> On 09.09.14 09:31, Eric Auger wrote:
>>> A new common module is created. It implements all functions
>>> that have no device specificity (PCI, Platform).
>>>
>>> This patch only consists in move (no functional changes)
>>>
>>> Signed-off-by: Kim Phillips <kim.phillips@linaro.org>
>>> Signed-off-by: Eric Auger <eric.auger@linaro.org>
>>>
>>> ---
>>> v5 -> v6:
>>> - follow all evolutions of original PCI code from v5 to V6
>>> - move declaration of vfio_region_ops, vfio_memory_listener,
>>>   vfio_group_list, vfio_address_spaces into vfio-common.h
>>>
>>> v4 -> v5:
>>> - integrate "sPAPR/IOMMU: Fix TCE entry permission"
>>> - VFIOdevice .name dealloc removed from vfio_put_base_device
>>> - add some includes according to vfio inclusion policy
>>>
>>> v3 -> v4:
>>> [Eric Auger]
>>> move done after all PCI modifications to anticipate for
>>> VFIO Platform needs. Purpose is to alleviate the whole
>>> review process.
>>>
>>> <= v3
>>> First split done by Kim Phillips
>>> ---
>>>  hw/vfio/Makefile.objs         |    1 +
>>>  hw/vfio/common.c              |  958 ++++++++++++++++++++++++++++++++++++++
>>>  hw/vfio/pci.c                 | 1028 +----------------------------------------
>>>  include/hw/vfio/vfio-common.h |  152 ++++++
>>>  trace-events                  |    1 +
>>>  5 files changed, 1113 insertions(+), 1027 deletions(-)
>>>  create mode 100644 hw/vfio/common.c
>>>  create mode 100644 include/hw/vfio/vfio-common.h
>>>
>>> diff --git a/hw/vfio/Makefile.objs b/hw/vfio/Makefile.objs
>>> index 31c7dab..e31f30e 100644
>>> --- a/hw/vfio/Makefile.objs
>>> +++ b/hw/vfio/Makefile.objs
>>> @@ -1,3 +1,4 @@
>>>  ifeq ($(CONFIG_LINUX), y)
>>> +obj-$(CONFIG_SOFTMMU) += common.o
>>>  obj-$(CONFIG_PCI) += pci.o
>>>  endif
>>> diff --git a/hw/vfio/common.c b/hw/vfio/common.c
>>> new file mode 100644
>>> index 0000000..252c0b8
>>> --- /dev/null
>>> +++ b/hw/vfio/common.c
>>> @@ -0,0 +1,958 @@
>>> +/*
>>> + * generic functions used by VFIO devices
>>> + *
>>> + * Copyright Red Hat, Inc. 2012
>>> + *
>>> + * Authors:
>>> + *  Alex Williamson <alex.williamson@redhat.com>
>>> + *
>>> + * This work is licensed under the terms of the GNU GPL, version 2.  See
>>> + * the COPYING file in the top-level directory.
>>> + *
>>> + * Based on qemu-kvm device-assignment:
>>> + *  Adapted for 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)
>>> + *  Copyright (C) 2008, IBM, Muli Ben-Yehuda (muli@il.ibm.com)
>>> + */
>>> +
>>> +#include <sys/ioctl.h>
>>> +#include <sys/mman.h>
>>> +#include <linux/vfio.h>
>>> +
>>> +#include "hw/vfio/vfio-common.h"
>>> +#include "hw/vfio/vfio.h"
>>> +#include "exec/address-spaces.h"
>>> +#include "exec/memory.h"
>>> +#include "hw/hw.h"
>>> +#include "qemu/error-report.h"
>>> +#include "sysemu/kvm.h"
>>> +#include "trace.h"
>>> +
>>> +struct vfio_group_head vfio_group_list =
>>> +    QLIST_HEAD_INITIALIZER(vfio_address_spaces);
>>> +struct vfio_as_head vfio_address_spaces =
>>> +    QLIST_HEAD_INITIALIZER(vfio_address_spaces);
>>> +
>>> +#ifdef CONFIG_KVM
>>> +/*
>>> + * We have a single VFIO pseudo device per KVM VM.  Once created it lives
>>> + * for the life of the VM.  Closing the file descriptor only drops our
>>> + * reference to it and the device's reference to kvm.  Therefore once
>>> + * initialized, this file descriptor is only released on QEMU exit and
>>> + * we'll re-use it should another vfio device be attached before then.
>>> + */
>>> +static int vfio_kvm_device_fd = -1;
>>> +#endif
>>> +
>>> +/*
>>> + * Common VFIO interrupt disable
>>> + */
>>> +void vfio_disable_irqindex(VFIODevice *vbasedev, int index)
>>> +{
>>> +    struct vfio_irq_set irq_set = {
>>> +        .argsz = sizeof(irq_set),
>>> +        .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_TRIGGER,
>>> +        .index = index,
>>> +        .start = 0,
>>> +        .count = 0,
>>> +    };
>>> +
>>> +    ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
>>> +}
>>> +
>>> +void vfio_unmask_irqindex(VFIODevice *vbasedev, int index)
>>> +{
>>> +    struct vfio_irq_set irq_set = {
>>> +        .argsz = sizeof(irq_set),
>>> +        .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_UNMASK,
>>> +        .index = index,
>>> +        .start = 0,
>>> +        .count = 1,
>>> +    };
>>> +
>>> +    ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
>>> +}
>>> +
>>> +void vfio_mask_irqindex(VFIODevice *vbasedev, int index)
>>> +{
>>> +    struct vfio_irq_set irq_set = {
>>> +        .argsz = sizeof(irq_set),
>>> +        .flags = VFIO_IRQ_SET_DATA_NONE | VFIO_IRQ_SET_ACTION_MASK,
>>> +        .index = index,
>>> +        .start = 0,
>>> +        .count = 1,
>>> +    };
>>> +
>>> +    ioctl(vbasedev->fd, VFIO_DEVICE_SET_IRQS, &irq_set);
>>> +}
>>> +
>>> +/*
>>> + * IO Port/MMIO - Beware of the endians, VFIO is always little endian
>>> + */
>>> +void vfio_region_write(void *opaque, hwaddr addr,
>>> +                       uint64_t data, unsigned size)
>>> +{
>>> +    VFIORegion *region = opaque;
>>> +    VFIODevice *vbasedev = region->vbasedev;
>>> +    union {
>>> +        uint8_t byte;
>>> +        uint16_t word;
>>> +        uint32_t dword;
>>> +        uint64_t qword;
>>> +    } buf;
>>> +
>>> +    switch (size) {
>>> +    case 1:
>>> +        buf.byte = data;
>>> +        break;
>>> +    case 2:
>>> +        buf.word = data;
>>> +        break;
>>> +    case 4:
>>> +        buf.dword = data;
>>
>> Please beware that this code is affected by Alexey's patch set that
>> fixes endianness for slow patch MMIO access and ROM regions.
> 
> Hi Alex,
> 
> do you mean vfio_region_write/read implementation will be different
> depending on whether we are on PCI or platform; or simply I need to pay
> attention to the fact this code will need an upgrade with Alexey's patch
> ( [PATCH 0/2] vfio: Another try to fix ROM BAR endianness).

You will simply need an update when Alexey's patches are in. I don't see
why vfio-platform should be any different from vfio-pci here.


Alex