> On 20 Feb 2019, at 08:58, Zhao Yan <yan.y.zhao@xxxxxxxxx> wrote:
>
> On Tue, Feb 19, 2019 at 03:42:36PM +0100, Christophe de Dinechin wrote:
>>
>>
>>> On 19 Feb 2019, at 09:53, Yan Zhao <yan.y.zhao@xxxxxxxxx> wrote:
>>>
>>> If a device has device memory capability, save/load data from device memory
>>> in pre-copy and stop-and-copy phases.
>>>
>>> LOGGING state is set for device memory for dirty page logging:
>>> in LOGGING state, get device memory returns whole device memory snapshot;
>>> outside LOGGING state, get device memory returns dirty data since last get
>>> operation.
>>>
>>> Usually, device memory is very big, qemu needs to chunk it into several
>>> pieces each with size of device memory region.
>>>
>>> Signed-off-by: Yan Zhao <yan.y.zhao@xxxxxxxxx>
>>> Signed-off-by: Kirti Wankhede <kwankhede@xxxxxxxxxx>
>>> ---
>>> hw/vfio/migration.c | 235 ++++++++++++++++++++++++++++++++++++++++++++++++++--
>>> hw/vfio/pci.h | 1 +
>>> 2 files changed, 231 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
>>> index 16d6395..f1e9309 100644
>>> --- a/hw/vfio/migration.c
>>> +++ b/hw/vfio/migration.c
>>> @@ -203,6 +203,201 @@ static int vfio_load_data_device_config(VFIOPCIDevice *vdev,
>>> return 0;
>>> }
>>>
>>> +static int vfio_get_device_memory_size(VFIOPCIDevice *vdev)
>>> +{
>>> + VFIODevice *vbasedev = &vdev->vbasedev;
>>> + VFIORegion *region_ctl =
>>> + &vdev->migration->region[VFIO_DEVSTATE_REGION_CTL];
>>> + uint64_t len;
>>> + int sz;
>>> +
>>> + sz = sizeof(len);
>>> + if (pread(vbasedev->fd, &len, sz,
>>> + region_ctl->fd_offset +
>>> + offsetof(struct vfio_device_state_ctl, device_memory.size))
>>> + != sz) {
>>> + error_report("vfio: Failed to get length of device memory”);
>>
>> s/length/size/ ? (to be consistent with function name)
>
> ok. thanks
>>> + return -1;
>>> + }
>>> + vdev->migration->devmem_size = len;
>>> + return 0;
>>> +}
>>> +
>>> +static int vfio_set_device_memory_size(VFIOPCIDevice *vdev, uint64_t size)
>>> +{
>>> + VFIODevice *vbasedev = &vdev->vbasedev;
>>> + VFIORegion *region_ctl =
>>> + &vdev->migration->region[VFIO_DEVSTATE_REGION_CTL];
>>> + int sz;
>>> +
>>> + sz = sizeof(size);
>>> + if (pwrite(vbasedev->fd, &size, sz,
>>> + region_ctl->fd_offset +
>>> + offsetof(struct vfio_device_state_ctl, device_memory.size))
>>> + != sz) {
>>> + error_report("vfio: Failed to set length of device comemory”);
>>
>> What is comemory? Typo?
>
> Right, typo. should be "memory" :)
>>
>> Same comment about length vs size
>>
> got it. thanks
>
>>> + return -1;
>>> + }
>>> + vdev->migration->devmem_size = size;
>>> + return 0;
>>> +}
>>> +
>>> +static
>>> +int vfio_save_data_device_memory_chunk(VFIOPCIDevice *vdev, QEMUFile *f,
>>> + uint64_t pos, uint64_t len)
>>> +{
>>> + VFIODevice *vbasedev = &vdev->vbasedev;
>>> + VFIORegion *region_ctl =
>>> + &vdev->migration->region[VFIO_DEVSTATE_REGION_CTL];
>>> + VFIORegion *region_devmem =
>>> + &vdev->migration->region[VFIO_DEVSTATE_REGION_DATA_DEVICE_MEMORY];
>>> + void *dest;
>>> + uint32_t sz;
>>> + uint8_t *buf = NULL;
>>> + uint32_t action = VFIO_DEVICE_DATA_ACTION_GET_BUFFER;
>>> +
>>> + if (len > region_devmem->size) {
>>
>> Is it intentional that there is no error_report here?
>>
> an error_report here may be better.
>>> + return -1;
>>> + }
>>> +
>>> + sz = sizeof(pos);
>>> + if (pwrite(vbasedev->fd, &pos, sz,
>>> + region_ctl->fd_offset +
>>> + offsetof(struct vfio_device_state_ctl, device_memory.pos))
>>> + != sz) {
>>> + error_report("vfio: Failed to set save buffer pos");
>>> + return -1;
>>> + }
>>> + sz = sizeof(action);
>>> + if (pwrite(vbasedev->fd, &action, sz,
>>> + region_ctl->fd_offset +
>>> + offsetof(struct vfio_device_state_ctl, device_memory.action))
>>> + != sz) {
>>> + error_report("vfio: Failed to set save buffer action");
>>> + return -1;
>>> + }
>>> +
>>> + if (!vfio_device_state_region_mmaped(region_devmem)) {
>>> + buf = g_malloc(len);
>>> + if (buf == NULL) {
>>> + error_report("vfio: Failed to allocate memory for migrate”);
>> s/migrate/migration/ ?
>
> yes, thanks
>>> + return -1;
>>> + }
>>> + if (pread(vbasedev->fd, buf, len, region_devmem->fd_offset) != len) {
>>> + error_report("vfio: error load device memory buffer”);
>> s/load/loading/ ?
> error to load? :)
I’d check with a native speaker, but I believe it’s “error loading”.
To me (to be checked), the two sentences don’t have the same meaning:
“It is an error to load device memory buffer” -> “You are not allowed to do that”
“I had an error loading device memory buffer” -> “I tried, but it failed"
>
>>> + return -1;
>>> + }
>>> + qemu_put_be64(f, len);
>>> + qemu_put_be64(f, pos);
>>> + qemu_put_buffer(f, buf, len);
>>> + g_free(buf);
>>> + } else {
>>> + dest = region_devmem->mmaps[0].mmap;
>>> + qemu_put_be64(f, len);
>>> + qemu_put_be64(f, pos);
>>> + qemu_put_buffer(f, dest, len);
>>> + }
>>> + return 0;
>>> +}
>>> +
>>> +static int vfio_save_data_device_memory(VFIOPCIDevice *vdev, QEMUFile *f)
>>> +{
>>> + VFIORegion *region_devmem =
>>> + &vdev->migration->region[VFIO_DEVSTATE_REGION_DATA_DEVICE_MEMORY];
>>> + uint64_t total_len = vdev->migration->devmem_size;
>>> + uint64_t pos = 0;
>>> +
>>> + qemu_put_be64(f, total_len);
>>> + while (pos < total_len) {
>>> + uint64_t len = region_devmem->size;
>>> +
>>> + if (pos + len >= total_len) {
>>> + len = total_len - pos;
>>> + }
>>> + if (vfio_save_data_device_memory_chunk(vdev, f, pos, len)) {
>>> + return -1;
>>> + }
>>
>> I don’t see where pos is incremented in this loop
>>
> yes, missing one line "pos += len;"
> Currently, code is not verified in hardware with device memory cap on.
> Thanks:)
>>> + }
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +static
>>> +int vfio_load_data_device_memory_chunk(VFIOPCIDevice *vdev, QEMUFile *f,
>>> + uint64_t pos, uint64_t len)
>>> +{
>>> + VFIODevice *vbasedev = &vdev->vbasedev;
>>> + VFIORegion *region_ctl =
>>> + &vdev->migration->region[VFIO_DEVSTATE_REGION_CTL];
>>> + VFIORegion *region_devmem =
>>> + &vdev->migration->region[VFIO_DEVSTATE_REGION_DATA_DEVICE_MEMORY];
>>> +
>>> + void *dest;
>>> + uint32_t sz;
>>> + uint8_t *buf = NULL;
>>> + uint32_t action = VFIO_DEVICE_DATA_ACTION_SET_BUFFER;
>>> +
>>> + if (len > region_devmem->size) {
>>
>> error_report?
>
> seems better to add error_report.
>>> + return -1;
>>> + }
>>> +
>>> + sz = sizeof(pos);
>>> + if (pwrite(vbasedev->fd, &pos, sz,
>>> + region_ctl->fd_offset +
>>> + offsetof(struct vfio_device_state_ctl, device_memory.pos))
>>> + != sz) {
>>> + error_report("vfio: Failed to set device memory buffer pos");
>>> + return -1;
>>> + }
>>> + if (!vfio_device_state_region_mmaped(region_devmem)) {
>>> + buf = g_malloc(len);
>>> + if (buf == NULL) {
>>> + error_report("vfio: Failed to allocate memory for migrate");
>>> + return -1;
>>> + }
>>> + qemu_get_buffer(f, buf, len);
>>> + if (pwrite(vbasedev->fd, buf, len,
>>> + region_devmem->fd_offset) != len) {
>>> + error_report("vfio: Failed to load devie memory buffer");
>>> + return -1;
>>> + }
>>> + g_free(buf);
>>> + } else {
>>> + dest = region_devmem->mmaps[0].mmap;
>>> + qemu_get_buffer(f, dest, len);
>>> + }
>>> +
>>> + sz = sizeof(action);
>>> + if (pwrite(vbasedev->fd, &action, sz,
>>> + region_ctl->fd_offset +
>>> + offsetof(struct vfio_device_state_ctl, device_memory.action))
>>> + != sz) {
>>> + error_report("vfio: Failed to set load device memory buffer action");
>>> + return -1;
>>> + }
>>> +
>>> + return 0;
>>> +
>>> +}
>>> +
>>> +static int vfio_load_data_device_memory(VFIOPCIDevice *vdev,
>>> + QEMUFile *f, uint64_t total_len)
>>> +{
>>> + uint64_t pos = 0, len = 0;
>>> +
>>> + vfio_set_device_memory_size(vdev, total_len);
>>> +
>>> + while (pos + len < total_len) {
>>> + len = qemu_get_be64(f);
>>> + pos = qemu_get_be64(f);
>>
>> Nit: load reads len/pos in the loop, whereas save does it in the
>> inner function (vfio_save_data_device_memory_chunk)
> right, load has to read len/pos in the loop.
>>
>>> +
>>> + vfio_load_data_device_memory_chunk(vdev, f, pos, len);
>>> + }
>>> +
>>> + return 0;
>>> +}
>>> +
>>> +
>>> static int vfio_set_dirty_page_bitmap_chunk(VFIOPCIDevice *vdev,
>>> uint64_t start_addr, uint64_t page_nr)
>>> {
>>> @@ -377,6 +572,10 @@ static void vfio_save_live_pending(QEMUFile *f, void *opaque,
>>> return;
>>> }
>>>
>>> + /* get dirty data size of device memory */
>>> + vfio_get_device_memory_size(vdev);
>>> +
>>> + *res_precopy_only += vdev->migration->devmem_size;
>>> return;
>>> }
>>>
>>> @@ -388,7 +587,9 @@ static int vfio_save_iterate(QEMUFile *f, void *opaque)
>>> return 0;
>>> }
>>>
>>> - return 0;
>>> + qemu_put_byte(f, VFIO_SAVE_FLAG_DEVMEMORY);
>>> + /* get dirty data of device memory */
>>> + return vfio_save_data_device_memory(vdev, f);
>>> }
>>>
>>> static void vfio_pci_load_config(VFIOPCIDevice *vdev, QEMUFile *f)
>>> @@ -458,6 +659,10 @@ static int vfio_load_state(QEMUFile *f, void *opaque, int version_id)
>>> len = qemu_get_be64(f);
>>> vfio_load_data_device_config(vdev, f, len);
>>> break;
>>> + case VFIO_SAVE_FLAG_DEVMEMORY:
>>> + len = qemu_get_be64(f);
>>> + vfio_load_data_device_memory(vdev, f, len);
>>> + break;
>>> default:
>>> ret = -EINVAL;
>>> }
>>> @@ -503,6 +708,13 @@ static int vfio_save_complete_precopy(QEMUFile *f, void *opaque)
>>> VFIOPCIDevice *vdev = opaque;
>>> int rc = 0;
>>>
>>> + if (vfio_device_data_cap_device_memory(vdev)) {
>>> + qemu_put_byte(f, VFIO_SAVE_FLAG_DEVMEMORY | VFIO_SAVE_FLAG_CONTINUE);
>>> + /* get dirty data of device memory */
>>> + vfio_get_device_memory_size(vdev);
>>> + rc = vfio_save_data_device_memory(vdev, f);
>>> + }
>>> +
>>> qemu_put_byte(f, VFIO_SAVE_FLAG_PCI | VFIO_SAVE_FLAG_CONTINUE);
>>> vfio_pci_save_config(vdev, f);
>>>
>>> @@ -515,12 +727,22 @@ static int vfio_save_complete_precopy(QEMUFile *f, void *opaque)
>>>
>>> static int vfio_save_setup(QEMUFile *f, void *opaque)
>>> {
>>> + int rc = 0;
>>> VFIOPCIDevice *vdev = opaque;
>>> - qemu_put_byte(f, VFIO_SAVE_FLAG_SETUP);
>>> +
>>> + if (vfio_device_data_cap_device_memory(vdev)) {
>>> + qemu_put_byte(f, VFIO_SAVE_FLAG_SETUP | VFIO_SAVE_FLAG_CONTINUE);
>>> + qemu_put_byte(f, VFIO_SAVE_FLAG_DEVMEMORY);
>>> + /* get whole snapshot of device memory */
>>> + vfio_get_device_memory_size(vdev);
>>> + rc = vfio_save_data_device_memory(vdev, f);
>>> + } else {
>>> + qemu_put_byte(f, VFIO_SAVE_FLAG_SETUP);
>>> + }
>>>
>>> vfio_set_device_state(vdev, VFIO_DEVICE_STATE_RUNNING |
>>> VFIO_DEVICE_STATE_LOGGING);
>>> - return 0;
>>> + return rc;
>>> }
>>>
>>> static int vfio_load_setup(QEMUFile *f, void *opaque)
>>> @@ -576,8 +798,11 @@ int vfio_migration_init(VFIOPCIDevice *vdev, Error **errp)
>>> goto error;
>>> }
>>>
>>> - if (vfio_device_data_cap_device_memory(vdev)) {
>>> - error_report("No suppport of data cap device memory Yet");
>>> + if (vfio_device_data_cap_device_memory(vdev) &&
>>> + vfio_device_state_region_setup(vdev,
>>> + &vdev->migration->region[VFIO_DEVSTATE_REGION_DATA_DEVICE_MEMORY],
>>> + VFIO_REGION_SUBTYPE_DEVICE_STATE_DATA_MEMORY,
>>> + "device-state-data-device-memory")) {
>>> goto error;
>>> }
>>>
>>> diff --git a/hw/vfio/pci.h b/hw/vfio/pci.h
>>> index 4b7b1bb..a2cc64b 100644
>>> --- a/hw/vfio/pci.h
>>> +++ b/hw/vfio/pci.h
>>> @@ -69,6 +69,7 @@ typedef struct VFIOMigration {
>>> uint32_t data_caps;
>>> uint32_t device_state;
>>> uint64_t devconfig_size;
>>> + uint64_t devmem_size;
>>> VMChangeStateEntry *vm_state;
>>> } VFIOMigration;
>>>
>>> --
>>> 2.7.4
>>>
>>> _______________________________________________
>>> intel-gvt-dev mailing list
>>> intel-gvt-dev@xxxxxxxxxxxxxxxxxxxxx
>>> https://lists.freedesktop.org/mailman/listinfo/intel-gvt-dev
>>
>> _______________________________________________
>> intel-gvt-dev mailing list
>> intel-gvt-dev@xxxxxxxxxxxxxxxxxxxxx
>> https://lists.freedesktop.org/mailman/listinfo/intel-gvt-dev
