On 02/13/2015 04:06 AM, Vladimir Sementsov-Ogievskiy wrote:
+
+ blk_mig_reset_dirty_cursor();
+ dirty_phase(f, false);
+
+ QSIMPLEQ_FOREACH(dbms, &dirty_bitmap_mig_state.dbms_list, entry) {
+ uint8_t flags = DIRTY_BITMAP_MIG_FLAG_DEVICE_NAME |
+ DIRTY_BITMAP_MIG_FLAG_BITMAP_NAME |
+ DIRTY_BITMAP_MIG_FLAG_ENABLED;
+
+ qemu_put_byte(f, flags);
+ qemu_put_name(f, bdrv_get_device_name(dbms->bs));
+ qemu_put_name(f, bdrv_dirty_bitmap_name(dbms->bitmap));
+ qemu_put_byte(f, bdrv_dirty_bitmap_enabled(dbms->bitmap));
+ }
+
+ qemu_put_byte(f, DIRTY_BITMAP_MIG_FLAG_EOS);
+
+ DPRINTF("Dirty bitmaps migration completed\n");
+
+ dirty_bitmap_mig_cleanup();
+ return 0;
+}
+
I suppose we don't need a flag that distinctly SAYS this is the end
section, since we can tell by omission of
DIRTY_BITMAP_MIG_FLAG_NORMAL_CHUNK or ZERO_CHUNK.
Hmm. I think it simplifies the logic (to use EOS after each section).
And the same approach is in migration/block.c.. It's a question about
which format is better: "Each section for dirty_bitmap_load ends with
EOS" or "Each section for dirty_bitmap_load ends with EOS except the
last one. The last one may be recognized by absent NORMAL_CHUNK and
ZERO_CHUNK"
Oh, sorry, no, it's important EOS. There are several blocks with no
*_CHUNK! Several bitmaps. And loop in dirty_bitmap_load will read them
iteratively, and it will finish when find EOS.
Sorry, I worded that poorly. I was wondering why you didn't have an
explicit "end of bitmap" flag, and I realized that you are doing this
check essentially by the absence of the NORMAL_CHUNK/ZERO_CHUNK flags.
This is really just a comment on my part; I was expecting a more
distinct "It is now safe to rebuild the bitmap" flag and was just
commenting on why we didn't necessarily need one.
I think in another comment I point out that an "end of bitmap" flag
might make the loading function simpler, and I still think that might be
nice.
