On 7/22/2019 2:09 PM, Yan Zhao wrote:
> On Tue, Jul 09, 2019 at 05:49:18PM +0800, Kirti Wankhede wrote:
>> Dirty page tracking (.log_sync) is part of RAM copying state, where
>> vendor driver provides the bitmap of pages which are dirtied by vendor
>> driver through migration region and as part of RAM copy, those pages
>> gets copied to file stream.
>>
>> To get dirty page bitmap:
>> - write start address, page_size and pfn count.
>> - read count of pfns copied.
>> - Vendor driver should return 0 if driver doesn't have any page to
>> report dirty in given range.
>> - Vendor driver should return -1 to mark all pages dirty for given range.
>> - read data_offset, where vendor driver has written bitmap.
>> - read bitmap from the region or mmaped part of the region.
>> - Iterate above steps till page bitmap for all requested pfns are copied.
>>
>> Signed-off-by: Kirti Wankhede <kwankh...@nvidia.com>
>> Reviewed-by: Neo Jia <c...@nvidia.com>
>> ---
>> hw/vfio/migration.c | 123
>> ++++++++++++++++++++++++++++++++++++++++++
>> hw/vfio/trace-events | 1 +
>> include/hw/vfio/vfio-common.h | 2 +
>> 3 files changed, 126 insertions(+)
>>
>> diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c
>> index 5fb4c5329ede..ca1a8c0f5f1f 100644
>> --- a/hw/vfio/migration.c
>> +++ b/hw/vfio/migration.c
>> @@ -269,6 +269,129 @@ static int vfio_load_device_config_state(QEMUFile *f,
>> void *opaque)
>> return qemu_file_get_error(f);
>> }
>>
>> +void vfio_get_dirty_page_list(VFIODevice *vbasedev,
>> + uint64_t start_pfn,
>> + uint64_t pfn_count,
>> + uint64_t page_size)
>> +{
>> + VFIOMigration *migration = vbasedev->migration;
>> + VFIORegion *region = &migration->region.buffer;
>> + uint64_t count = 0;
>> + int64_t copied_pfns = 0;
>> + int64_t total_pfns = pfn_count;
>> + int ret;
>> +
>> + qemu_mutex_lock(&migration->lock);
>> +
>> + while (total_pfns > 0) {
>> + uint64_t bitmap_size, data_offset = 0;
>> + uint64_t start = start_pfn + count;
>> + void *buf = NULL;
>> + bool buffer_mmaped = false;
>> +
>> + ret = pwrite(vbasedev->fd, &start, sizeof(start),
>> + region->fd_offset + offsetof(struct
>> vfio_device_migration_info,
>> + start_pfn));
>> + if (ret < 0) {
>> + error_report("%s: Failed to set dirty pages start address %d
>> %s",
>> + vbasedev->name, ret, strerror(errno));
>> + goto dpl_unlock;
>> + }
>> +
>> + ret = pwrite(vbasedev->fd, &page_size, sizeof(page_size),
>> + region->fd_offset + offsetof(struct
>> vfio_device_migration_info,
>> + page_size));
>> + if (ret < 0) {
>> + error_report("%s: Failed to set dirty page size %d %s",
>> + vbasedev->name, ret, strerror(errno));
>> + goto dpl_unlock;
>> + }
>> +
>> + ret = pwrite(vbasedev->fd, &total_pfns, sizeof(total_pfns),
>> + region->fd_offset + offsetof(struct
>> vfio_device_migration_info,
>> + total_pfns));
>> + if (ret < 0) {
>> + error_report("%s: Failed to set dirty page total pfns %d %s",
>> + vbasedev->name, ret, strerror(errno));
>> + goto dpl_unlock;
>> + }
>> +
>> + /* Read copied dirty pfns */
>> + ret = pread(vbasedev->fd, &copied_pfns, sizeof(copied_pfns),
>> + region->fd_offset + offsetof(struct
>> vfio_device_migration_info,
>> + copied_pfns));
>> + if (ret < 0) {
>> + error_report("%s: Failed to get dirty pages bitmap count %d %s",
>> + vbasedev->name, ret, strerror(errno));
>> + goto dpl_unlock;
>> + }
>> +
>> + if (copied_pfns == VFIO_DEVICE_DIRTY_PFNS_NONE) {
>> + /*
>> + * copied_pfns could be 0 if driver doesn't have any page to
>> + * report dirty in given range
>> + */
>> + break;
>> + } else if (copied_pfns == VFIO_DEVICE_DIRTY_PFNS_ALL) {
>> + /* Mark all pages dirty for this range */
>> + cpu_physical_memory_set_dirty_range(start_pfn * page_size,
>> + pfn_count * page_size,
>> + DIRTY_MEMORY_MIGRATION);
>> + break;
>> + }
>> +
>> + bitmap_size = (BITS_TO_LONGS(copied_pfns) + 1) * sizeof(unsigned
>> long);
> hi Kirti
>
> why bitmap_size is
> (BITS_TO_LONGS(copied_pfns) + 1) * sizeof(unsigned long).
> why it's not
> BITS_TO_LONGS(copied_pfns) * sizeof(unsigned long) ?
>
It should be later. I'll update in next version.
Thanks,
Kirti
> Thanks
> Yan
>
>> + ret = pread(vbasedev->fd, &data_offset, sizeof(data_offset),
>> + region->fd_offset + offsetof(struct
>> vfio_device_migration_info,
>> + data_offset));
>> + if (ret != sizeof(data_offset)) {
>> + error_report("%s: Failed to get migration buffer data offset
>> %d",
>> + vbasedev->name, ret);
>> + goto dpl_unlock;
>> + }
>> +
>> + if (region->mmaps) {
>> + buf = find_data_region(region, data_offset, bitmap_size);
>> + }
>> +
>> + buffer_mmaped = (buf != NULL) ? true : false;
>> +
>> + if (!buffer_mmaped) {
>> + buf = g_try_malloc0(bitmap_size);
>> + if (!buf) {
>> + error_report("%s: Error allocating buffer ", __func__);
>> + goto dpl_unlock;
>> + }
>> +
>> + ret = pread(vbasedev->fd, buf, bitmap_size,
>> + region->fd_offset + data_offset);
>> + if (ret != bitmap_size) {
>> + error_report("%s: Failed to get dirty pages bitmap %d",
>> + vbasedev->name, ret);
>> + g_free(buf);
>> + goto dpl_unlock;
>> + }
>> + }
>> +
>> + cpu_physical_memory_set_dirty_lebitmap((unsigned long *)buf,
>> + (start_pfn + count) *
>> page_size,
>> + copied_pfns);
>> + count += copied_pfns;
>> + total_pfns -= copied_pfns;
>> +
>> + if (!buffer_mmaped) {
>> + g_free(buf);
>> + }
>> + }
>> +
>> + trace_vfio_get_dirty_page_list(vbasedev->name, start_pfn, pfn_count,
>> + page_size);
>> +
>> +dpl_unlock:
>> + qemu_mutex_unlock(&migration->lock);
>> +}
>> +
>> /* ---------------------------------------------------------------------- */
>>
>> static int vfio_save_setup(QEMUFile *f, void *opaque)
>> diff --git a/hw/vfio/trace-events b/hw/vfio/trace-events
>> index ac065b559f4e..414a5e69ec5e 100644
>> --- a/hw/vfio/trace-events
>> +++ b/hw/vfio/trace-events
>> @@ -160,3 +160,4 @@ vfio_save_complete_precopy(char *name) " (%s)"
>> vfio_load_device_config_state(char *name) " (%s)"
>> vfio_load_state(char *name, uint64_t data) " (%s) data 0x%"PRIx64
>> vfio_load_state_device_data(char *name, uint64_t data_offset, uint64_t
>> data_size) " (%s) Offset 0x%"PRIx64" size 0x%"PRIx64
>> +vfio_get_dirty_page_list(char *name, uint64_t start, uint64_t pfn_count,
>> uint64_t page_size) " (%s) start 0x%"PRIx64" pfn_count 0x%"PRIx64 " page
>> size 0x%"PRIx64
>> diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h
>> index a022484d2636..dc1b83a0b4ef 100644
>> --- a/include/hw/vfio/vfio-common.h
>> +++ b/include/hw/vfio/vfio-common.h
>> @@ -222,5 +222,7 @@ int vfio_spapr_remove_window(VFIOContainer *container,
>>
>> int vfio_migration_probe(VFIODevice *vbasedev, Error **errp);
>> void vfio_migration_finalize(VFIODevice *vbasedev);
>> +void vfio_get_dirty_page_list(VFIODevice *vbasedev, uint64_t start_pfn,
>> + uint64_t pfn_count, uint64_t page_size);
>>
>> #endif /* HW_VFIO_VFIO_COMMON_H */
>> --
>> 2.7.0
>>
>
