Message ID | 1561041461-22326-11-git-send-email-kwankhede@nvidia.com |
---|---|
State | New |
Headers | show |
Series | Add migration support for VFIO device | expand |
On Thu, Jun 20, 2019 at 10:37:38PM +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. This copy is > iterated till page bitmap for all requested pfns are copied. > > Signed-off-by: Kirti Wankhede <kwankhede@nvidia.com> > Reviewed-by: Neo Jia <cjia@nvidia.com> > --- > hw/vfio/migration.c | 119 ++++++++++++++++++++++++++++++++++++++++++ > include/hw/vfio/vfio-common.h | 2 + > 2 files changed, 121 insertions(+) > > diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c > index e4895f91761d..68775b5dec11 100644 > --- a/hw/vfio/migration.c > +++ b/hw/vfio/migration.c > @@ -228,6 +228,125 @@ 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; > + int ret; > + > + qemu_mutex_lock(&migration->lock); > + ret = pwrite(vbasedev->fd, &start_pfn, sizeof(start_pfn), > + region->fd_offset + offsetof(struct vfio_device_migration_info, > + start_pfn)); > + if (ret < 0) { > + error_report("Failed to set dirty pages start address %d %s", > + 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("Failed to set dirty page size %d %s", > + ret, strerror(errno)); > + goto dpl_unlock; > + } > + > + ret = pwrite(vbasedev->fd, &pfn_count, sizeof(pfn_count), > + region->fd_offset + offsetof(struct vfio_device_migration_info, > + total_pfns)); > + if (ret < 0) { > + error_report("Failed to set dirty page total pfns %d %s", > + ret, strerror(errno)); > + goto dpl_unlock; > + } > + > + do { > + uint64_t bitmap_size, data_offset = 0; > + void *buf = NULL; > + bool buffer_mmaped = false; > + > + /* 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("Failed to get dirty pages bitmap count %d %s", > + ret, strerror(errno)); > + goto dpl_unlock; > + } > + > + if (copied_pfns == 0) { > + /* > + * copied_pfns could be 0 if driver doesn't have any page to > + * report dirty in given range > + */ > + break; this copied_pfn is the dirty page count in which range? if it is got each iteration, why break here rather than continue ? consider there's a big region with pfn_count, and it is now breaked into several smaller subregions, and copied_pfns is 0 in the first subregion, it doesn't mean copied_pfns are all 0 in the remaining subregions. > + } else if (copied_pfns == -1) { > + /* 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); > + > + 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("Failed to get migration buffer data offset %d", > + ret); > + goto dpl_unlock; > + } > + > + if (region->mmaps) { > + int i; > + for (i = 0; i < region->nr_mmaps; i++) { > + if ((region->mmaps[i].offset >= data_offset) && > + (data_offset < region->mmaps[i].offset + > + region->mmaps[i].size)) { > + buf = region->mmaps[i].mmap + (data_offset - > + region->mmaps[i].offset); > + buffer_mmaped = true; > + break; > + } > + } > + } > + > + if (!buffer_mmaped) { > + buf = g_malloc0(bitmap_size); > + > + ret = pread(vbasedev->fd, buf, bitmap_size, > + region->fd_offset + data_offset); > + if (ret != bitmap_size) { > + error_report("Failed to get dirty pages bitmap %d", 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; > + here also. why it is count += copied_pfns. > + if (!buffer_mmaped) { > + g_free(buf); > + } > + } while (count < pfn_count); > + > +dpl_unlock: > + qemu_mutex_unlock(&migration->lock); > +} > + > /* ---------------------------------------------------------------------- */ > > static int vfio_save_setup(QEMUFile *f, void *opaque) > diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h > index 1d26e6be8d48..423d6dbccace 100644 > --- a/include/hw/vfio/vfio-common.h > +++ b/include/hw/vfio/vfio-common.h > @@ -224,5 +224,7 @@ 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 >
diff --git a/hw/vfio/migration.c b/hw/vfio/migration.c index e4895f91761d..68775b5dec11 100644 --- a/hw/vfio/migration.c +++ b/hw/vfio/migration.c @@ -228,6 +228,125 @@ 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; + int ret; + + qemu_mutex_lock(&migration->lock); + ret = pwrite(vbasedev->fd, &start_pfn, sizeof(start_pfn), + region->fd_offset + offsetof(struct vfio_device_migration_info, + start_pfn)); + if (ret < 0) { + error_report("Failed to set dirty pages start address %d %s", + 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("Failed to set dirty page size %d %s", + ret, strerror(errno)); + goto dpl_unlock; + } + + ret = pwrite(vbasedev->fd, &pfn_count, sizeof(pfn_count), + region->fd_offset + offsetof(struct vfio_device_migration_info, + total_pfns)); + if (ret < 0) { + error_report("Failed to set dirty page total pfns %d %s", + ret, strerror(errno)); + goto dpl_unlock; + } + + do { + uint64_t bitmap_size, data_offset = 0; + void *buf = NULL; + bool buffer_mmaped = false; + + /* 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("Failed to get dirty pages bitmap count %d %s", + ret, strerror(errno)); + goto dpl_unlock; + } + + if (copied_pfns == 0) { + /* + * copied_pfns could be 0 if driver doesn't have any page to + * report dirty in given range + */ + break; + } else if (copied_pfns == -1) { + /* 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); + + 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("Failed to get migration buffer data offset %d", + ret); + goto dpl_unlock; + } + + if (region->mmaps) { + int i; + for (i = 0; i < region->nr_mmaps; i++) { + if ((region->mmaps[i].offset >= data_offset) && + (data_offset < region->mmaps[i].offset + + region->mmaps[i].size)) { + buf = region->mmaps[i].mmap + (data_offset - + region->mmaps[i].offset); + buffer_mmaped = true; + break; + } + } + } + + if (!buffer_mmaped) { + buf = g_malloc0(bitmap_size); + + ret = pread(vbasedev->fd, buf, bitmap_size, + region->fd_offset + data_offset); + if (ret != bitmap_size) { + error_report("Failed to get dirty pages bitmap %d", 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; + + if (!buffer_mmaped) { + g_free(buf); + } + } while (count < pfn_count); + +dpl_unlock: + qemu_mutex_unlock(&migration->lock); +} + /* ---------------------------------------------------------------------- */ static int vfio_save_setup(QEMUFile *f, void *opaque) diff --git a/include/hw/vfio/vfio-common.h b/include/hw/vfio/vfio-common.h index 1d26e6be8d48..423d6dbccace 100644 --- a/include/hw/vfio/vfio-common.h +++ b/include/hw/vfio/vfio-common.h @@ -224,5 +224,7 @@ 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 */