[Qemu-devel] [PATCH 2/9] mirror: create mirror_dirty_init helper for mirror_run

["Denis V. Lunev" <den@openvz.org>]

The code inside the helper will be extended in the next patch. mirror_run
itself is overbloated at the moment.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reviewed-by: Vladimir Sementsov-Ogievskiy<vsementsov@virtuozzo.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
CC: Fam Zheng <famz@redhat.com>
CC: Kevin Wolf <kwolf@redhat.com>
CC: Max Reitz <mreitz@redhat.com>
CC: Jeff Cody <jcody@redhat.com>
CC: Eric Blake <eblake@redhat.com>
---
 block/mirror.c | 83 ++++++++++++++++++++++++++++++++++------------------------
 1 file changed, 49 insertions(+), 34 deletions(-)

diff --git a/block/mirror.c b/block/mirror.c
index 3760e29..797659d 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -501,19 +501,62 @@ static void mirror_exit(BlockJob *job, void *opaque)
     bdrv_unref(src);
 }
 
+static int mirror_dirty_init(MirrorBlockJob *s)
+{
+    int64_t sector_num, end;
+    BlockDriverState *base = s->base;
+    BlockDriverState *bs = blk_bs(s->common.blk);
+    BlockDriverState *target_bs = blk_bs(s->target);
+    bool mark_all_dirty = base == NULL && !bdrv_has_zero_init(target_bs);
+    uint64_t last_pause_ns;
+    int ret, n;
+
+    end = s->bdev_length / BDRV_SECTOR_SIZE;
+
+    last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
+
+    /* First part, loop on the sectors and initialize the dirty bitmap.  */
+    for (sector_num = 0; sector_num < end; ) {
+        /* Just to make sure we are not exceeding int limit. */
+        int nb_sectors = MIN(INT_MAX >> BDRV_SECTOR_BITS,
+                             end - sector_num);
+        int64_t now = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
+
+        if (now - last_pause_ns > SLICE_TIME) {
+            last_pause_ns = now;
+            block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, 0);
+        }
+
+        if (block_job_is_cancelled(&s->common)) {
+            return 0;
+        }
+
+        ret = bdrv_is_allocated_above(bs, base, sector_num, nb_sectors, &n);
+        if (ret < 0) {
+            return ret;
+        }
+
+        assert(n > 0);
+        if (ret == 1 || mark_all_dirty) {
+            bdrv_set_dirty_bitmap(s->dirty_bitmap, sector_num, n);
+        }
+        sector_num += n;
+    }
+    return 0;
+}
+
 static void coroutine_fn mirror_run(void *opaque)
 {
     MirrorBlockJob *s = opaque;
     MirrorExitData *data;
     BlockDriverState *bs = blk_bs(s->common.blk);
     BlockDriverState *target_bs = blk_bs(s->target);
-    int64_t sector_num, end, length;
+    int64_t length;
     uint64_t last_pause_ns;
     BlockDriverInfo bdi;
     char backing_filename[2]; /* we only need 2 characters because we are only
                                  checking for a NULL string */
     int ret = 0;
-    int n;
     int target_cluster_size = BDRV_SECTOR_SIZE;
 
     if (block_job_is_cancelled(&s->common)) {
@@ -555,7 +598,6 @@ static void coroutine_fn mirror_run(void *opaque)
     s->target_cluster_sectors = target_cluster_size >> BDRV_SECTOR_BITS;
     s->max_iov = MIN(bs->bl.max_iov, target_bs->bl.max_iov);
 
-    end = s->bdev_length / BDRV_SECTOR_SIZE;
     s->buf = qemu_try_blockalign(bs, s->buf_size);
     if (s->buf == NULL) {
         ret = -ENOMEM;
@@ -564,41 +606,14 @@ static void coroutine_fn mirror_run(void *opaque)
 
     mirror_free_init(s);
 
-    last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
     if (!s->is_none_mode) {
-        /* First part, loop on the sectors and initialize the dirty bitmap.  */
-        BlockDriverState *base = s->base;
-        bool mark_all_dirty = s->base == NULL && !bdrv_has_zero_init(target_bs);
-
-        for (sector_num = 0; sector_num < end; ) {
-            /* Just to make sure we are not exceeding int limit. */
-            int nb_sectors = MIN(INT_MAX >> BDRV_SECTOR_BITS,
-                                 end - sector_num);
-            int64_t now = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
-
-            if (now - last_pause_ns > SLICE_TIME) {
-                last_pause_ns = now;
-                block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, 0);
-            }
-
-            if (block_job_is_cancelled(&s->common)) {
-                goto immediate_exit;
-            }
-
-            ret = bdrv_is_allocated_above(bs, base, sector_num, nb_sectors, &n);
-
-            if (ret < 0) {
-                goto immediate_exit;
-            }
-
-            assert(n > 0);
-            if (ret == 1 || mark_all_dirty) {
-                bdrv_set_dirty_bitmap(s->dirty_bitmap, sector_num, n);
-            }
-            sector_num += n;
+        ret = mirror_dirty_init(s);
+        if (ret < 0 || block_job_is_cancelled(&s->common)) {
+            goto immediate_exit;
         }
     }
 
+    last_pause_ns = qemu_clock_get_ns(QEMU_CLOCK_REALTIME);
     bdrv_dirty_iter_init(s->dirty_bitmap, &s->hbi);
     for (;;) {
         uint64_t delay_ns = 0;
-- 
2.5.0