From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:45903) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1bPFbQ-0006Mg-EF for qemu-devel@nongnu.org; Mon, 18 Jul 2016 16:57:27 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1bPFbO-0001JP-76 for qemu-devel@nongnu.org; Mon, 18 Jul 2016 16:57:23 -0400 From: John Snow Date: Mon, 18 Jul 2016 16:57:05 -0400 Message-Id: <1468875431-16646-5-git-send-email-jsnow@redhat.com> In-Reply-To: <1468875431-16646-1-git-send-email-jsnow@redhat.com> References: <1468875431-16646-1-git-send-email-jsnow@redhat.com> Subject: [Qemu-devel] [PATCH v7 04/10] block: Support meta dirty bitmap List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org Cc: vsementsov@virtuozzo.com, famz@redhat.com, qemu-devel@nongnu.org, mreitz@redhat.com, John Snow From: Fam Zheng The added group of operations enables tracking of the changed bits in the dirty bitmap. Signed-off-by: Fam Zheng Reviewed-by: Max Reitz Signed-off-by: John Snow --- block/dirty-bitmap.c | 52 ++++++++++++++++++++++++++++++++++++++++++++ include/block/dirty-bitmap.h | 9 ++++++++ 2 files changed, 61 insertions(+) diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c index 628b77c..970677c 100644 --- a/block/dirty-bitmap.c +++ b/block/dirty-bitmap.c @@ -38,6 +38,7 @@ */ struct BdrvDirtyBitmap { HBitmap *bitmap; /* Dirty sector bitmap implementation */ + HBitmap *meta; /* Meta dirty bitmap */ BdrvDirtyBitmap *successor; /* Anonymous child; implies frozen status */ char *name; /* Optional non-empty unique ID */ int64_t size; /* Size of the bitmap (Number of sectors) */ @@ -103,6 +104,56 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs, return bitmap; } +/* bdrv_create_meta_dirty_bitmap + * + * Create a meta dirty bitmap that tracks the changes of bits in @bitmap. I.e. + * when a dirty status bit in @bitmap is changed (either from reset to set or + * the other way around), its respective meta dirty bitmap bit will be marked + * dirty as well. + * + * @bitmap: the block dirty bitmap for which to create a meta dirty bitmap. + * @chunk_size: how many bytes of bitmap data does each bit in the meta bitmap + * track. + */ +void bdrv_create_meta_dirty_bitmap(BdrvDirtyBitmap *bitmap, + int chunk_size) +{ + assert(!bitmap->meta); + bitmap->meta = hbitmap_create_meta(bitmap->bitmap, + chunk_size * BITS_PER_BYTE); +} + +void bdrv_release_meta_dirty_bitmap(BdrvDirtyBitmap *bitmap) +{ + assert(bitmap->meta); + hbitmap_free_meta(bitmap->bitmap); + bitmap->meta = NULL; +} + +int bdrv_dirty_bitmap_get_meta(BlockDriverState *bs, + BdrvDirtyBitmap *bitmap, int64_t sector, + int nb_sectors) +{ + uint64_t i; + int gran = hbitmap_granularity(bitmap->meta); + + /* To optimize: we can make hbitmap to internally check the range in a + * coarse level, or at least do it word by word. */ + for (i = sector; i < sector + nb_sectors; i += gran) { + if (hbitmap_get(bitmap->meta, i)) { + return true; + } + } + return false; +} + +void bdrv_dirty_bitmap_reset_meta(BlockDriverState *bs, + BdrvDirtyBitmap *bitmap, int64_t sector, + int nb_sectors) +{ + hbitmap_reset(bitmap->meta, sector, nb_sectors); +} + bool bdrv_dirty_bitmap_frozen(BdrvDirtyBitmap *bitmap) { return bitmap->successor; @@ -233,6 +284,7 @@ static void bdrv_do_release_matching_dirty_bitmap(BlockDriverState *bs, if ((!bitmap || bm == bitmap) && (!only_named || bm->name)) { assert(!bm->active_iterators); assert(!bdrv_dirty_bitmap_frozen(bm)); + assert(!bm->meta); QLIST_REMOVE(bm, list); hbitmap_free(bm->bitmap); g_free(bm->name); diff --git a/include/block/dirty-bitmap.h b/include/block/dirty-bitmap.h index 2ea601b..50e0fca 100644 --- a/include/block/dirty-bitmap.h +++ b/include/block/dirty-bitmap.h @@ -8,6 +8,9 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs, uint32_t granularity, const char *name, Error **errp); +void bdrv_create_meta_dirty_bitmap(BdrvDirtyBitmap *bitmap, + int chunk_size); +void bdrv_release_meta_dirty_bitmap(BdrvDirtyBitmap *bitmap); int bdrv_dirty_bitmap_create_successor(BlockDriverState *bs, BdrvDirtyBitmap *bitmap, Error **errp); @@ -36,6 +39,12 @@ void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap, int64_t cur_sector, int nr_sectors); void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap, int64_t cur_sector, int nr_sectors); +int bdrv_dirty_bitmap_get_meta(BlockDriverState *bs, + BdrvDirtyBitmap *bitmap, int64_t sector, + int nb_sectors); +void bdrv_dirty_bitmap_reset_meta(BlockDriverState *bs, + BdrvDirtyBitmap *bitmap, int64_t sector, + int nb_sectors); BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap, uint64_t first_sector); void bdrv_dirty_iter_free(BdrvDirtyBitmapIter *iter); -- 2.7.4