On 07/24/2014 11:51 AM, Eric Auger wrote:
> On 07/09/2014 12:43 AM, Alex Williamson wrote:
>> On Mon, 2014-07-07 at 13:27 +0100, Eric Auger wrote:
>>> vfio_get_device now takes a VFIODevice as argument. The function is split
>>> into 4 functional parts: dev_info query, device check, region populate
>>> and interrupt populate. the last 3 are specialized by parent device and
>>> are added into DeviceOps.
>>>
>>> 3 new fields are introduced in VFIODevice to store dev_info.
>>>
>>> vfio_put_base_device is created.
>>>
>>> Signed-off-by: Eric Auger <eric.au...@linaro.org>
>>> ---
>>> hw/vfio/pci.c | 181
>>> +++++++++++++++++++++++++++++++++++++++-------------------
>>> 1 file changed, 121 insertions(+), 60 deletions(-)
>>>
>>> diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
>>> index 5f0164a..d228cf8 100644
>>> --- a/hw/vfio/pci.c
>>> +++ b/hw/vfio/pci.c
>>> @@ -194,12 +194,18 @@ typedef struct VFIODevice {
>>> bool reset_works;
>>> bool needs_reset;
>>> VFIODeviceOps *ops;
>>> + unsigned int num_irqs;
>>> + unsigned int num_regions;
>>> + unsigned int flags;
>>> } VFIODevice;
>>>
>>> struct VFIODeviceOps {
>>> bool (*vfio_compute_needs_reset)(VFIODevice *vdev);
>>> int (*vfio_hot_reset_multi)(VFIODevice *vdev);
>>> void (*vfio_eoi)(VFIODevice *vdev);
>>> + int (*vfio_check_device)(VFIODevice *vdev);
>>> + int (*vfio_populate_regions)(VFIODevice *vdev);
>>> + int (*vfio_populate_interrupts)(VFIODevice *vdev);
>>> };
>>>
>>> typedef struct VFIOPCIDevice {
>>> @@ -286,6 +292,10 @@ static uint32_t vfio_pci_read_config(PCIDevice *pdev,
>>> uint32_t addr, int len);
>>> static void vfio_pci_write_config(PCIDevice *pdev, uint32_t addr,
>>> uint32_t val, int len);
>>> static void vfio_mmap_set_enabled(VFIOPCIDevice *vdev, bool enabled);
>>> +static void vfio_put_base_device(VFIODevice *vbasedev);
>>> +static int vfio_check_device(VFIODevice *vbasedev);
>>> +static int vfio_populate_regions(VFIODevice *vbasedev);
>>> +static int vfio_populate_interrupts(VFIODevice *vbasedev);
>>>
>>> /*
>>> * Common VFIO interrupt disable
>>> @@ -3585,6 +3595,9 @@ static VFIODeviceOps vfio_pci_ops = {
>>> .vfio_compute_needs_reset = vfio_pci_compute_needs_reset,
>>> .vfio_hot_reset_multi = vfio_pci_hot_reset_multi,
>>> .vfio_eoi = vfio_eoi,
>>> + .vfio_check_device = vfio_check_device,
>>> + .vfio_populate_regions = vfio_populate_regions,
>>> + .vfio_populate_interrupts = vfio_populate_interrupts,
>>> };
>>>
>>> static void vfio_reset_handler(void *opaque)
>>> @@ -3927,54 +3940,53 @@ static void vfio_put_group(VFIOGroup *group)
>>> }
>>> }
>>>
>>> -static int vfio_get_device(VFIOGroup *group, const char *name,
>>> - VFIOPCIDevice *vdev)
>>> +static int vfio_check_device(VFIODevice *vbasedev)
>>> {
>>> - struct vfio_device_info dev_info = { .argsz = sizeof(dev_info) };
>>> - struct vfio_region_info reg_info = { .argsz = sizeof(reg_info) };
>>> - struct vfio_irq_info irq_info = { .argsz = sizeof(irq_info) };
>>> - int ret, i;
>>> -
>>> - ret = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name);
>>> - if (ret < 0) {
>>> - error_report("vfio: error getting device %s from group %d: %m",
>>> - name, group->groupid);
>>> - error_printf("Verify all devices in group %d are bound to vfio-pci
>>> "
>>> - "or pci-stub and not already in use\n",
>>> group->groupid);
>>> - return ret;
>>> + if (!(vbasedev->flags & VFIO_DEVICE_FLAGS_PCI)) {
>>> + error_report("vfio: Um, this isn't a PCI device");
>>> + goto error;
>>> }
>>> -
>>> - vdev->vbasedev.fd = ret;
>>> - vdev->vbasedev.group = group;
>>> - QLIST_INSERT_HEAD(&group->device_list, &vdev->vbasedev, next);
>>> -
>>> - /* Sanity check device */
>>> - ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_GET_INFO, &dev_info);
>>> - if (ret) {
>>> - error_report("vfio: error getting device info: %m");
>>> + if (vbasedev->num_regions < VFIO_PCI_CONFIG_REGION_INDEX + 1) {
>>> + error_report("vfio: unexpected number of io regions %u",
>>> + vbasedev->num_regions);
>>> goto error;
>>> }
>>> -
>>> - DPRINTF("Device %s flags: %u, regions: %u, irgs: %u\n", name,
>>> - dev_info.flags, dev_info.num_regions, dev_info.num_irqs);
>>> -
>>> - if (!(dev_info.flags & VFIO_DEVICE_FLAGS_PCI)) {
>>> - error_report("vfio: Um, this isn't a PCI device");
>>> + if (vbasedev->num_irqs < VFIO_PCI_MSIX_IRQ_INDEX + 1) {
>>> + error_report("vfio: unexpected number of irqs %u",
>>> + vbasedev->num_irqs);
>>> goto error;
>>> }
>>> + return 0;
>>> +error:
>>> + vfio_put_base_device(vbasedev);
>>
>> This doesn't make much sense, this function never "got" the base device,
>> so why does it need to "put" it on error? We should simply return error
>> and the caller (presumably who got it) should put the device.
> Hi Alex,
>
> definitively I need to revisit and homogenize my error handling: all
> sub-functions just returning errors - if sensible- , get/put at upper
> level. errno misusage. Sorry for that :-(
>>
>>> + return -errno;
>>
>> Nothing above seems to guarantee we have anything useful in errno (or
>> that it hasn't been clobbered).
> replaced by -1
>>
>>> +}
>>>
>>> - vdev->vbasedev.reset_works = !!(dev_info.flags &
>>> VFIO_DEVICE_FLAGS_RESET);
>>> +static int vfio_populate_interrupts(VFIODevice *vbasedev)
>>> +{
>>> + VFIOPCIDevice *vdev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
>>> + int ret;
>>> + struct vfio_irq_info irq_info = { .argsz = sizeof(irq_info) };
>>> + irq_info.index = VFIO_PCI_ERR_IRQ_INDEX;
>>>
>>> - if (dev_info.num_regions < VFIO_PCI_CONFIG_REGION_INDEX + 1) {
>>> - error_report("vfio: unexpected number of io regions %u",
>>> - dev_info.num_regions);
>>> - goto error;
>>> + ret = ioctl(vbasedev->fd, VFIO_DEVICE_GET_IRQ_INFO, &irq_info);
>>> + if (ret) {
>>> + /* This can fail for an old kernel or legacy PCI dev */
>>> + DPRINTF("VFIO_DEVICE_GET_IRQ_INFO failure: %m\n");
>>> + } else if (irq_info.count == 1) {
>>> + vdev->pci_aer = true;
>>> + } else {
>>> + error_report("vfio: %s Could not enable error recovery for the
>>> device",
>>> + vbasedev->name);
>>> }
>>> + return ret;
>>
>> This function returns error if the device doesn't support error
>> reporting, which is an optional feature. I don't think that's what we
>> want.
> OK misunderstood the comment. function proto changed to return void.
after some more thoughts related to platform usage I would like to keep
the return value and set it to 0 for PCI.
BR
Eric
>>
>>> +}
>>>
>>> - if (dev_info.num_irqs < VFIO_PCI_MSIX_IRQ_INDEX + 1) {
>>> - error_report("vfio: unexpected number of irqs %u",
>>> dev_info.num_irqs);
>>> - goto error;
>>> - }
>>> +static int vfio_populate_regions(VFIODevice *vbasedev)
>>> +{
>>> + struct vfio_region_info reg_info = { .argsz = sizeof(reg_info) };
>>> + int i, ret;
>>> + VFIOPCIDevice *vdev = container_of(vbasedev, VFIOPCIDevice, vbasedev);
>>>
>>> for (i = VFIO_PCI_BAR0_REGION_INDEX; i < VFIO_PCI_ROM_REGION_INDEX;
>>> i++) {
>>> reg_info.index = i;
>>> @@ -4018,7 +4030,7 @@ static int vfio_get_device(VFIOGroup *group, const
>>> char *name,
>>> vdev->config_offset = reg_info.offset;
>>>
>>> if ((vdev->features & VFIO_FEATURE_ENABLE_VGA) &&
>>> - dev_info.num_regions > VFIO_PCI_VGA_REGION_INDEX) {
>>> + vbasedev->num_regions > VFIO_PCI_VGA_REGION_INDEX) {
>>> struct vfio_region_info vga_info = {
>>> .argsz = sizeof(vga_info),
>>> .index = VFIO_PCI_VGA_REGION_INDEX,
>>> @@ -4057,38 +4069,87 @@ static int vfio_get_device(VFIOGroup *group, const
>>> char *name,
>>>
>>> vdev->has_vga = true;
>>> }
>>> - irq_info.index = VFIO_PCI_ERR_IRQ_INDEX;
>>> + return 0;
>>> +error:
>>> + vfio_put_base_device(vbasedev);
>>> + return -errno;
>>
>> errno can get clobbered by here, don't count on it. Also, why does this
>> put the base device while interrupt_populate error does not? The put
>> needs to happen a level above these functions imho.
>
> ok
>>
>>> +}
>>> +
>>> +static int vfio_get_device(VFIOGroup *group, const char *name,
>>> + VFIODevice *vbasedev)
>>> +{
>>> + struct vfio_device_info dev_info = { .argsz = sizeof(dev_info) };
>>> + struct vfio_region_info reg_info = { .argsz = sizeof(reg_info) };
>>> + struct vfio_irq_info irq_info = { .argsz = sizeof(irq_info) };
>>> + int ret;
>>> +
>>> + ret = ioctl(group->fd, VFIO_GROUP_GET_DEVICE_FD, name);
>>> + if (ret < 0) {
>>> + error_report("vfio: error getting device %s from group %d: %m",
>>> + name, group->groupid);
>>> + error_printf("Verify all devices in group %d are bound to vfio-pci
>>> "
>>> + "or pci-stub and not already in use\n",
>>> group->groupid);
>>> + return ret;
>>> + }
>>> +
>>> + vbasedev->fd = ret;
>>> + vbasedev->group = group;
>>> + QLIST_INSERT_HEAD(&group->device_list, vbasedev, next);
>>>
>>> - ret = ioctl(vdev->vbasedev.fd, VFIO_DEVICE_GET_IRQ_INFO, &irq_info);
>>> + ret = ioctl(vbasedev->fd, VFIO_DEVICE_GET_INFO, &dev_info);
>>> if (ret) {
>>> - /* This can fail for an old kernel or legacy PCI dev */
>>> - DPRINTF("VFIO_DEVICE_GET_IRQ_INFO failure: %m\n");
>>> - ret = 0;
>>> - } else if (irq_info.count == 1) {
>>> - vdev->pci_aer = true;
>>> - } else {
>>> - error_report("vfio: %04x:%02x:%02x.%x "
>>> - "Could not enable error recovery for the device",
>>> - vdev->host.domain, vdev->host.bus, vdev->host.slot,
>>> - vdev->host.function);
>>> + error_report("vfio: error getting device info: %m");
>>> + goto error;
>>> + }
>>> +
>>> + vbasedev->num_irqs = dev_info.num_irqs;
>>> + vbasedev->num_regions = dev_info.num_regions;
>>> + vbasedev->flags = dev_info.flags;
>>> +
>>> + DPRINTF("Device %s flags: %u, regions: %u, irgs: %u\n", name,
>>> + dev_info.flags, dev_info.num_regions, dev_info.num_irqs);
>>> +
>>> + vbasedev->reset_works = !!(dev_info.flags & VFIO_DEVICE_FLAGS_RESET);
>>> +
>>> + /* call device specific functions */
>>> + ret = vbasedev->ops->vfio_check_device(vbasedev);
>>> + if (ret) {
>>> + error_report("vfio: error when checking device %s\n",
>>> + vbasedev->name);
>>> + goto error;
>>> + }
>>> + ret = vbasedev->ops->vfio_populate_regions(vbasedev);
>>> + if (ret) {
>>> + error_report("vfio: error when populating regions of device %s\n",
>>> + vbasedev->name);
>>> + goto error;
>>> + }
>>> + ret = vbasedev->ops->vfio_populate_interrupts(vbasedev);
>>> + if (ret) {
>>> + error_report("vfio: error when populating interrupts of device
>>> %s\n",
>>> + vbasedev->name);
>>> + goto error;
>>> }
>>>
>>> error:
>>> if (ret) {
>>> - QLIST_REMOVE(&vdev->vbasedev, next);
>>> - vdev->vbasedev.group = NULL;
>>> - close(vdev->vbasedev.fd);
>>> + vfio_put_base_device(vbasedev);
>>
>> Whoops, more confusion, the call-out functions are doing put calls
>> (well, some of them) and so is this. This is the only place it should
>> occur.
> OK
>>
>>> }
>>> return ret;
>>> }
>>>
>>> -static void vfio_put_device(VFIOPCIDevice *vdev)
>>> +void vfio_put_base_device(VFIODevice *vbasedev)
>>> {
>>> - QLIST_REMOVE(&vdev->vbasedev, next);
>>> - vdev->vbasedev.group = NULL;
>>> + QLIST_REMOVE(vbasedev, next);
>>> + vbasedev->group = NULL;
>>> DPRINTF("vfio_put_device: close vdev->fd\n");
>>> - close(vdev->vbasedev.fd);
>>> - g_free(vdev->vbasedev.name);
>>> + close(vbasedev->fd);
>>> + g_free(vbasedev->name);
>>
>> get/put of the base device is still a bit messy. .name doesn't get
>> allocated by the get, but gets freed by the put.
>
> .name dealloc moved to vfio_put_device
>
> Thank you for your review
>
> Best Regards
>
> Eric
>>
>>> +}
>>> +
>>> +static void vfio_put_device(VFIOPCIDevice *vdev)
>>> +{
>>> + vfio_put_base_device(&vdev->vbasedev);
>>> if (vdev->msix) {
>>> g_free(vdev->msix);
>>> vdev->msix = NULL;
>>> @@ -4266,7 +4327,7 @@ static int vfio_initfn(PCIDevice *pdev)
>>> }
>>> }
>>>
>>> - ret = vfio_get_device(group, path, vdev);
>>> + ret = vfio_get_device(group, path, &vdev->vbasedev);
>>> if (ret) {
>>> error_report("vfio: failed to get device %s", path);
>>> vfio_put_group(group);
>>
>>
>>
>
