From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([208.118.235.92]:35035) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eRgd5-0003uh-Ou for qemu-devel@nongnu.org; Wed, 20 Dec 2017 10:50:05 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eRgd1-0005da-9y for qemu-devel@nongnu.org; Wed, 20 Dec 2017 10:49:58 -0500 From: Vladimir Sementsov-Ogievskiy Date: Wed, 20 Dec 2017 18:49:34 +0300 Message-Id: <20171220154945.88410-3-vsementsov@virtuozzo.com> In-Reply-To: <20171220154945.88410-1-vsementsov@virtuozzo.com> References: <20171220154945.88410-1-vsementsov@virtuozzo.com> Subject: [Qemu-devel] [PATCH v9 02/13] block/dirty-bitmap: fix locking in bdrv_reclaim_dirty_bitmap List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-block@nongnu.org, qemu-devel@nongnu.org Cc: pbonzini@redhat.com, armbru@redhat.com, eblake@redhat.com, famz@redhat.com, stefanha@redhat.com, amit.shah@redhat.com, quintela@redhat.com, mreitz@redhat.com, kwolf@redhat.com, peter.maydell@linaro.org, dgilbert@redhat.com, den@openvz.org, jsnow@redhat.com, vsementsov@virtuozzo.com, lirans@il.ibm.com Like other setters here these functions should take a lock. Signed-off-by: Vladimir Sementsov-Ogievskiy --- block/dirty-bitmap.c | 85 ++++++++++++++++++++++++++++++++-------------------- 1 file changed, 53 insertions(+), 32 deletions(-) diff --git a/block/dirty-bitmap.c b/block/dirty-bitmap.c index 81adbeb6d4..d83da077d5 100644 --- a/block/dirty-bitmap.c +++ b/block/dirty-bitmap.c @@ -245,6 +245,51 @@ void bdrv_dirty_bitmap_enable_successor(BdrvDirtyBitmap *bitmap) qemu_mutex_unlock(bitmap->mutex); } +/* Called within bdrv_dirty_bitmap_lock..unlock */ +static void bdrv_do_release_matching_dirty_bitmap_locked( + BlockDriverState *bs, BdrvDirtyBitmap *bitmap, + bool (*cond)(BdrvDirtyBitmap *bitmap)) +{ + BdrvDirtyBitmap *bm, *next; + + QLIST_FOREACH_SAFE(bm, &bs->dirty_bitmaps, list, next) { + if ((!bitmap || bm == bitmap) && (!cond || cond(bm))) { + 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); + g_free(bm); + + if (bitmap) { + return; + } + } + } + + if (bitmap) { + abort(); + } +} + +/* Called with BQL taken. */ +static void bdrv_do_release_matching_dirty_bitmap( + BlockDriverState *bs, BdrvDirtyBitmap *bitmap, + bool (*cond)(BdrvDirtyBitmap *bitmap)) +{ + bdrv_dirty_bitmaps_lock(bs); + bdrv_do_release_matching_dirty_bitmap_locked(bs, bitmap, cond); + bdrv_dirty_bitmaps_unlock(bs); +} + +/* Called within bdrv_dirty_bitmap_lock..unlock */ +static void bdrv_release_dirty_bitmap_locked(BlockDriverState *bs, + BdrvDirtyBitmap *bitmap) +{ + bdrv_do_release_matching_dirty_bitmap_locked(bs, bitmap, NULL); +} + /** * For a bitmap with a successor, yield our name to the successor, * delete the old bitmap, and return a handle to the new bitmap. @@ -286,7 +331,11 @@ BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *parent, Error **errp) { - BdrvDirtyBitmap *successor = parent->successor; + BdrvDirtyBitmap *successor; + + qemu_mutex_lock(parent->mutex); + + successor = parent->successor; if (!successor) { error_setg(errp, "Cannot reclaim a successor when none is present"); @@ -297,9 +346,11 @@ BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs, error_setg(errp, "Merging of parent and successor bitmap failed"); return NULL; } - bdrv_release_dirty_bitmap(bs, successor); + bdrv_release_dirty_bitmap_locked(bs, successor); parent->successor = NULL; + qemu_mutex_unlock(parent->mutex); + return parent; } @@ -327,36 +378,6 @@ static bool bdrv_dirty_bitmap_has_name(BdrvDirtyBitmap *bitmap) } /* Called with BQL taken. */ -static void bdrv_do_release_matching_dirty_bitmap( - BlockDriverState *bs, BdrvDirtyBitmap *bitmap, - bool (*cond)(BdrvDirtyBitmap *bitmap)) -{ - BdrvDirtyBitmap *bm, *next; - bdrv_dirty_bitmaps_lock(bs); - QLIST_FOREACH_SAFE(bm, &bs->dirty_bitmaps, list, next) { - if ((!bitmap || bm == bitmap) && (!cond || cond(bm))) { - 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); - g_free(bm); - - if (bitmap) { - goto out; - } - } - } - if (bitmap) { - abort(); - } - -out: - bdrv_dirty_bitmaps_unlock(bs); -} - -/* Called with BQL taken. */ void bdrv_release_dirty_bitmap(BlockDriverState *bs, BdrvDirtyBitmap *bitmap) { bdrv_do_release_matching_dirty_bitmap(bs, bitmap, NULL); -- 2.11.1