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make dirty-bitmap byte-based

PATCH Superseded Eric Blake 4 participants 32 messages Apr 12, 2017 – Apr 18, 2017 Block layer

v1 of 10 Superseded Latest is v10 →

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Eric Blake

author
#0 lore raw

cover make dirty-bitmap byte-based

There are patches floating around to add NBD_CMD_BLOCK_STATUS, but NBD wants to report status on byte granularity (even if the reporting will probably be naturally aligned to sectors or even much higher levels). I've therefore started the task of converting our block status code to report at a byte granularity rather than sectors.

This is part two of that conversion: dirty-bitmap. Other parts include bdrv_is_allocated (previously submitted) and replacing bdrv_get_block_status with a byte based callback in all the drivers (still being written).

Available as a tag at:
git fetch git://repo.or.cz/qemu/ericb.git nbd-byte-dirty-v1

It requires the following (v1 of bdrv_is_allocated, v9 of blkdebug, and Max's block-next tree):
https://lists.gnu.org/archive/html/qemu-devel/2017-04/msg01995.html
https://lists.gnu.org/archive/html/qemu-devel/2017-04/msg01723.html
https://lists.gnu.org/archive/html/qemu-devel/2017-04/msg01298.html

Eric Blake (12):
dirty-bitmap: Report BlockDirtyInfo.count in bytes, as documented
migration: Don't lose errno across aio context changes
dirty-bitmap: Drop unused functions
dirty-bitmap: Track size in bytes
dirty-bitmap: Set iterator start by offset, not sector
dirty-bitmap: Change bdrv_dirty_iter_next() to report byte offset
dirty-bitmap: Change bdrv_get_dirty_count() to report bytes
dirty-bitmap: Change bdrv_get_dirty() to take bytes
dirty-bitmap: Change bdrv_[re]set_dirty_bitmap() to use bytes
mirror: Switch mirror_dirty_init() to byte-based iteration
dirty-bitmap: Switch bdrv_set_dirty() to bytes
dirty-bitmap: Convert internal hbitmap size/granularity

 include/block/block_int.h    |  2 +-
 include/block/dirty-bitmap.h | 21 ++++-------
 block/backup.c               |  7 ++--
 block/dirty-bitmap.c         | 83 ++++++++++++--------------------------------
 block/io.c                   |  6 ++--
 block/mirror.c               | 73 +++++++++++++++++---------------------
 migration/block.c            | 14 ++++----
 7 files changed, 74 insertions(+), 132 deletions(-)
Signature · 1 line
2.9.3
author
#1 lore raw

PATCH 1/12 dirty-bitmap: Report BlockDirtyInfo.count in bytes, as documented

We've been documenting the value in bytes since its introduction in commit b9a9b3a4 (v1.3), where it was actually reported in bytes.

Commit e4654d2 (v2.0) then removed things from block/qapi.c, in preparation for a rewrite to a list of dirty sectors in the next commit 21b5683 in block.c, but the new code mistakenly started reporting in sectors.

---
Too late for 2.9, since the regression has been unnoticed for nine releases. But worth putting in 2.9.1.

---
 block/dirty-bitmap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
block/dirty-bitmap.c +1 -1
index 519737c..6d8ce5f 100644
@@ -345,7 +345,7 @@ BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
     QLIST_FOREACH(bm, &bs->dirty_bitmaps, list) {
         BlockDirtyInfo *info = g_new0(BlockDirtyInfo, 1);
         BlockDirtyInfoList *entry = g_new0(BlockDirtyInfoList, 1);
-        info->count = bdrv_get_dirty_count(bm);
+        info->count = bdrv_get_dirty_count(bm) << BDRV_SECTOR_BITS;
         info->granularity = bdrv_dirty_bitmap_granularity(bm);
         info->has_name = !!bm->name;
         info->name = g_strdup(bm->name);
Signature · 1 line
2.9.3
Reviewed-by on v1 1/12
#2 lore raw

Re: [Qemu-devel] [PATCH 01/12] dirty-bitmap: Report BlockDirtyInfo.count in bytes, as documented

Quoted 10 lines · Eric Blake

We've been documenting the value in bytes since its introduction in commit b9a9b3a4 (v1.3), where it was actually reported in bytes.

Commit e4654d2 (v2.0) then removed things from block/qapi.c, in preparation for a rewrite to a list of dirty sectors in the next commit 21b5683 in block.c, but the new code mistakenly started reporting in sectors.

Quoted 7 lines

---
Too late for 2.9, since the regression has been unnoticed for nine releases. But worth putting in 2.9.1.
---

Since before I started working here :)

I even documented the wrong thing in my two talks on the matter, but I suppose I never committed it to bitmaps.md, so...

I guess this is technically correct?

http://i3.kym-cdn.com/photos/images/facebook/000/909/991/48c.jpg

Quoted 9 lines
 block/dirty-bitmap.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
block/dirty-bitmap.c +0 -0
index 519737c..6d8ce5f 100644

block/dirty-bitmap.c BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs) · line 351

Quoted 8 lines
block/dirty-bitmap.c +1 -1
@@ -345,7 +345,7 @@ BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
     QLIST_FOREACH(bm, &bs->dirty_bitmaps, list) {
         BlockDirtyInfo *info = g_new0(BlockDirtyInfo, 1);
         BlockDirtyInfoList *entry = g_new0(BlockDirtyInfoList, 1);
-        info->count = bdrv_get_dirty_count(bm);
+        info->count = bdrv_get_dirty_count(bm) << BDRV_SECTOR_BITS;
         info->granularity = bdrv_dirty_bitmap_granularity(bm);
         info->has_name = !!bm->name;
         info->name = g_strdup(bm->name);

This is strictly more useful than sectors anyway, so ...

author
#3 lore raw

PATCH 2/12 migration: Don't lose errno across aio context changes

In reply to Eric Blake

set_drity_tracking() was assuming that the errno value set by bdrv_create_dirty_bitmap() would not be corrupted by either blk_get_aio_context() or aio_context_release(). Rather than audit whether this assumption is safe, rewrite the code to just grab the value of errno sooner.

---
 migration/block.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
migration/block.c +1 -1
index 18d50ff..9a9c214 100644
@@ -350,9 +350,9 @@ static int set_dirty_tracking(void)
         aio_context_acquire(blk_get_aio_context(bmds->blk));
         bmds->dirty_bitmap = bdrv_create_dirty_bitmap(blk_bs(bmds->blk),
                                                       BLOCK_SIZE, NULL, NULL);
+        ret = -errno;
         aio_context_release(blk_get_aio_context(bmds->blk));
         if (!bmds->dirty_bitmap) {
-            ret = -errno;
             goto fail;
         }
     }
Signature · 1 line
2.9.3
Reviewed-by on v1 2/12
#4 lore raw

Re: [Qemu-devel] [PATCH 02/12] migration: Don't lose errno across aio context changes

Quoted 1 line · Eric Blake

set_drity_tracking() was assuming that the errno value set by

*cough*

Quoted 17 lines

bdrv_create_dirty_bitmap() would not be corrupted by either blk_get_aio_context() or aio_context_release(). Rather than audit whether this assumption is safe, rewrite the code to just grab the value of errno sooner.

---
 migration/block.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
migration/block.c +0 -0
index 18d50ff..9a9c214 100644

migration/block.c static int set_dirty_tracking(void) · line 358

Quoted 10 lines
migration/block.c +1 -1
@@ -350,9 +350,9 @@ static int set_dirty_tracking(void)
         aio_context_acquire(blk_get_aio_context(bmds->blk));
         bmds->dirty_bitmap = bdrv_create_dirty_bitmap(blk_bs(bmds->blk),
                                                       BLOCK_SIZE, NULL, NULL);
+        ret = -errno;
         aio_context_release(blk_get_aio_context(bmds->blk));
         if (!bmds->dirty_bitmap) {
-            ret = -errno;
             goto fail;
         }
     }
Reviewed-by on v1 2/12
#5 lore raw

Re: [Qemu-devel] [PATCH 02/12] migration: Don't lose errno across aio context changes

In reply to Eric Blake
Quoted 8 lines · Eric Blake

set_drity_tracking() was assuming that the errno value set by bdrv_create_dirty_bitmap() would not be corrupted by either blk_get_aio_context() or aio_context_release(). Rather than audit whether this assumption is safe, rewrite the code to just grab the value of errno sooner.

author
#6 lore raw

PATCH 3/12 dirty-bitmap: Drop unused functions

In reply to Eric Blake

We had several functions that no one was using, and which used sector-based interfaces. I'm trying to convert towards byte-based interfaces, so it's easier to just drop the unused functions:

bdrv_dirty_bitmap_size
bdrv_dirty_bitmap_get_meta
bdrv_dirty_bitmap_reset_meta
bdrv_dirty_bitmap_meta_granularity

---
 include/block/dirty-bitmap.h |  8 --------
 block/dirty-bitmap.c         | 34 ----------------------------------
 2 files changed, 42 deletions(-)
include/block/dirty-bitmap.h +0 -8
index 9dea14b..a83979d 100644
@@ -30,11 +30,9 @@ void bdrv_enable_dirty_bitmap(BdrvDirtyBitmap *bitmap);
 BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs);
 uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs);
 uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap);
-uint32_t bdrv_dirty_bitmap_meta_granularity(BdrvDirtyBitmap *bitmap);
 bool bdrv_dirty_bitmap_enabled(BdrvDirtyBitmap *bitmap);
 bool bdrv_dirty_bitmap_frozen(BdrvDirtyBitmap *bitmap);
 const char *bdrv_dirty_bitmap_name(const BdrvDirtyBitmap *bitmap);
-int64_t bdrv_dirty_bitmap_size(const BdrvDirtyBitmap *bitmap);
 DirtyBitmapStatus bdrv_dirty_bitmap_status(BdrvDirtyBitmap *bitmap);
 int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
                    int64_t sector);
@@ -42,12 +40,6 @@ void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
                            int64_t cur_sector, int64_t nr_sectors);
 void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
                              int64_t cur_sector, int64_t 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_meta_iter_new(BdrvDirtyBitmap *bitmap);
 BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap,
                                          uint64_t first_sector);
block/dirty-bitmap.c +0 -34
index 6d8ce5f..32698d5 100644
@@ -130,35 +130,6 @@ void bdrv_release_meta_dirty_bitmap(BdrvDirtyBitmap *bitmap)
     bitmap->meta = NULL;
 }
 
-int bdrv_dirty_bitmap_get_meta(BlockDriverState *bs,
-                               BdrvDirtyBitmap *bitmap, int64_t sector,
-                               int nb_sectors)
-{
-    uint64_t i;
-    int sectors_per_bit = 1 << 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 += sectors_per_bit) {
-        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);
-}
-
-int64_t bdrv_dirty_bitmap_size(const BdrvDirtyBitmap *bitmap)
-{
-    return bitmap->size;
-}
-
 const char *bdrv_dirty_bitmap_name(const BdrvDirtyBitmap *bitmap)
 {
     return bitmap->name;
@@ -393,11 +364,6 @@ uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap)
     return BDRV_SECTOR_SIZE << hbitmap_granularity(bitmap->bitmap);
 }
 
-uint32_t bdrv_dirty_bitmap_meta_granularity(BdrvDirtyBitmap *bitmap)
-{
-    return BDRV_SECTOR_SIZE << hbitmap_granularity(bitmap->meta);
-}
-
 BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap,
                                          uint64_t first_sector)
 {
Signature · 1 line
2.9.3
#7 lore raw

Re: [Qemu-devel] [PATCH 03/12] dirty-bitmap: Drop unused functions

Quoted 87 lines · Eric Blake

We had several functions that no one was using, and which used sector-based interfaces. I'm trying to convert towards byte-based interfaces, so it's easier to just drop the unused functions:

bdrv_dirty_bitmap_size
bdrv_dirty_bitmap_get_meta
bdrv_dirty_bitmap_reset_meta
bdrv_dirty_bitmap_meta_granularity

---
 include/block/dirty-bitmap.h |  8 --------
 block/dirty-bitmap.c         | 34 ----------------------------------
 2 files changed, 42 deletions(-)
include/block/dirty-bitmap.h +0 -8
index 9dea14b..a83979d 100644
@@ -30,11 +30,9 @@ void bdrv_enable_dirty_bitmap(BdrvDirtyBitmap *bitmap);
 BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs);
 uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs);
 uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap);
-uint32_t bdrv_dirty_bitmap_meta_granularity(BdrvDirtyBitmap *bitmap);
 bool bdrv_dirty_bitmap_enabled(BdrvDirtyBitmap *bitmap);
 bool bdrv_dirty_bitmap_frozen(BdrvDirtyBitmap *bitmap);
 const char *bdrv_dirty_bitmap_name(const BdrvDirtyBitmap *bitmap);
-int64_t bdrv_dirty_bitmap_size(const BdrvDirtyBitmap *bitmap);
 DirtyBitmapStatus bdrv_dirty_bitmap_status(BdrvDirtyBitmap *bitmap);
 int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
                    int64_t sector);
@@ -42,12 +40,6 @@ void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
                            int64_t cur_sector, int64_t nr_sectors);
 void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
                              int64_t cur_sector, int64_t 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_meta_iter_new(BdrvDirtyBitmap *bitmap);
 BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap,
                                          uint64_t first_sector);
block/dirty-bitmap.c +0 -29
index 6d8ce5f..32698d5 100644
@@ -130,35 +130,6 @@ void bdrv_release_meta_dirty_bitmap(BdrvDirtyBitmap *bitmap)
     bitmap->meta = NULL;
 }
 
-int bdrv_dirty_bitmap_get_meta(BlockDriverState *bs,
-                               BdrvDirtyBitmap *bitmap, int64_t sector,
-                               int nb_sectors)
-{
-    uint64_t i;
-    int sectors_per_bit = 1 << 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 += sectors_per_bit) {
-        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);
-}
-
-int64_t bdrv_dirty_bitmap_size(const BdrvDirtyBitmap *bitmap)
-{
-    return bitmap->size;
-}
-
 const char *bdrv_dirty_bitmap_name(const BdrvDirtyBitmap *bitmap)
 {
     return bitmap->name;
@@ -393,11 +364,6 @@ uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap)
     return BDRV_SECTOR_SIZE << hbitmap_granularity(bitmap->bitmap);

block/dirty-bitmap.c uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap) · line 369

Quoted 10 lines
block/dirty-bitmap.c +0 -5
 }
 
-uint32_t bdrv_dirty_bitmap_meta_granularity(BdrvDirtyBitmap *bitmap)
-{
-    return BDRV_SECTOR_SIZE << hbitmap_granularity(bitmap->meta);
-}
-
 BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap,
                                          uint64_t first_sector)
 {

I think it's likely Vladimir is or at least was relying on some of these for his migration and persistence series.

Might be nice to let him chime in to see how much of a hassle this is.

author
#8 lore raw

Re: [Qemu-devel] [PATCH 03/12] dirty-bitmap: Drop unused functions

Quoted 20 lines · John Snow
Quoted 9 lines · Eric Blake

We had several functions that no one was using, and which used sector-based interfaces. I'm trying to convert towards byte-based interfaces, so it's easier to just drop the unused functions:

bdrv_dirty_bitmap_size
bdrv_dirty_bitmap_get_meta
bdrv_dirty_bitmap_reset_meta
bdrv_dirty_bitmap_meta_granularity

Quoted 6 lines
---
 include/block/dirty-bitmap.h |  8 --------
 block/dirty-bitmap.c         | 34 ----------------------------------
 2 files changed, 42 deletions(-)
Quoted 4 lines

I think it's likely Vladimir is or at least was relying on some of these for his migration and persistence series.

Might be nice to let him chime in to see how much of a hassle this is.

Then let's add him in cc ;)

I'm okay if these functions stay because they have a user, but it would also be nice if they were properly byte-based (like everything else in dirty-bitmap at the end of my series). So even if we remove them here, we can revert the removal, and re-add them but with a sane interface.

Signature · 3 lines
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org
#9 lore raw

Re: [Qemu-devel] [PATCH 03/12] dirty-bitmap: Drop unused functions

Quoted 21 lines · Eric Blake
Quoted 20 lines · John Snow
Quoted 15 lines · Eric Blake

We had several functions that no one was using, and which used sector-based interfaces. I'm trying to convert towards byte-based interfaces, so it's easier to just drop the unused functions:

bdrv_dirty_bitmap_size
bdrv_dirty_bitmap_get_meta
bdrv_dirty_bitmap_reset_meta
bdrv_dirty_bitmap_meta_granularity

---
 include/block/dirty-bitmap.h |  8 --------
 block/dirty-bitmap.c         | 34 ----------------------------------
 2 files changed, 42 deletions(-)
Quoted 7 lines
Quoted 4 lines

I think it's likely Vladimir is or at least was relying on some of these for his migration and persistence series.

Might be nice to let him chime in to see how much of a hassle this is.

Then let's add him in cc ;)

Err... I can't just summon people by mentioning them?

Quoted 5 lines

I'm okay if these functions stay because they have a user, but it would also be nice if they were properly byte-based (like everything else in dirty-bitmap at the end of my series). So even if we remove them here, we can revert the removal, and re-add them but with a sane interface.

OK, but I will offer to do the work in the interest of not slowing things down any further.

Do you use any of these, Vladimir?

--js

#10 lore raw

Re: [Qemu-devel] [PATCH 03/12] dirty-bitmap: Drop unused functions

Quoted 33 lines · John Snow
Quoted 18 lines · Eric Blake
Quoted 17 lines · John Snow
Quoted 15 lines · Eric Blake

We had several functions that no one was using, and which used sector-based interfaces. I'm trying to convert towards byte-based interfaces, so it's easier to just drop the unused functions:

bdrv_dirty_bitmap_size
bdrv_dirty_bitmap_get_meta
bdrv_dirty_bitmap_reset_meta
bdrv_dirty_bitmap_meta_granularity

---
  include/block/dirty-bitmap.h |  8 --------
  block/dirty-bitmap.c         | 34 ----------------------------------
  2 files changed, 42 deletions(-)
Quoted 6 lines
Quoted 4 lines

I think it's likely Vladimir is or at least was relying on some of these for his migration and persistence series.

Might be nice to let him chime in to see how much of a hassle this is.

Then let's add him in cc ;)

Err... I can't just summon people by mentioning them?

Quoted 5 lines

I'm okay if these functions stay because they have a user, but it would also be nice if they were properly byte-based (like everything else in dirty-bitmap at the end of my series). So even if we remove them here, we can revert the removal, and re-add them but with a sane interface.

Quoted 6 lines

OK, but I will offer to do the work in the interest of not slowing things down any further.

Do you use any of these, Vladimir?

--js

HI all!

only bdrv_dirty_bitmap_size() is used. No problem to add it back with my series next update

Signature · 2 lines
Best regards,
Vladimir
Reviewed-by
#11 lore raw

Re: [Qemu-devel] [PATCH 03/12] dirty-bitmap: Drop unused functions

Quoted 38 lines · Vladimir Sementsov-Ogievskiy
Quoted 37 lines · John Snow
Quoted 18 lines · Eric Blake
Quoted 17 lines · John Snow
Quoted 15 lines · Eric Blake

We had several functions that no one was using, and which used sector-based interfaces. I'm trying to convert towards byte-based interfaces, so it's easier to just drop the unused functions:

bdrv_dirty_bitmap_size
bdrv_dirty_bitmap_get_meta
bdrv_dirty_bitmap_reset_meta
bdrv_dirty_bitmap_meta_granularity

---
  include/block/dirty-bitmap.h |  8 --------
  block/dirty-bitmap.c         | 34 ----------------------------------
  2 files changed, 42 deletions(-)
Quoted 7 lines
Quoted 5 lines

I think it's likely Vladimir is or at least was relying on some of these
for his migration and persistence series.

Might be nice to let him chime in to see how much of a hassle this is.

Then let's add him in cc ;)

Err... I can't just summon people by mentioning them?

Quoted 5 lines

I'm okay if these functions stay because they have a user, but it would also be nice if they were properly byte-based (like everything else in dirty-bitmap at the end of my series). So even if we remove them here, we can revert the removal, and re-add them but with a sane interface.

OK, but I will offer to do the work in the interest of not slowing things down any further.

Quoted 9 lines
Quoted 3 lines

Do you use any of these, Vladimir?

--js

HI all!

only bdrv_dirty_bitmap_size() is used. No problem to add it back with my series next update

Excellent, thanks!

In that case:

Should be for the whole series, IIRC.

--js

author
#12 lore raw

PATCH 4/12 dirty-bitmap: Track size in bytes

In reply to Eric Blake

We are still using an internal hbitmap that tracks a size in sectors, with the granularity scaled down accordingly, because it lets us use a shortcut for our iterators which are currently sector-based. But there's no reason we can't track the dirty bitmap size in bytes, since it is an internal-only variable.

---
 block/dirty-bitmap.c | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)
block/dirty-bitmap.c +13 -10
index 32698d5..a413df1 100644
@@ -41,7 +41,7 @@ struct BdrvDirtyBitmap {
     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) */
+    int64_t size;               /* Size of the bitmap, in bytes */
     bool disabled;              /* Bitmap is read-only */
     int active_iterators;       /* How many iterators are active */
     QLIST_ENTRY(BdrvDirtyBitmap) list;
@@ -79,24 +79,26 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
 {
     int64_t bitmap_size;
     BdrvDirtyBitmap *bitmap;
-    uint32_t sector_granularity;
 
-    assert((granularity & (granularity - 1)) == 0);
+    assert(is_power_of_2(granularity) && granularity >= BDRV_SECTOR_SIZE);
 
     if (name && bdrv_find_dirty_bitmap(bs, name)) {
         error_setg(errp, "Bitmap already exists: %s", name);
         return NULL;
     }
-    sector_granularity = granularity >> BDRV_SECTOR_BITS;
-    assert(sector_granularity);
-    bitmap_size = bdrv_nb_sectors(bs);
+    bitmap_size = bdrv_getlength(bs);
     if (bitmap_size < 0) {
         error_setg_errno(errp, -bitmap_size, "could not get length of device");
         errno = -bitmap_size;
         return NULL;
     }
     bitmap = g_new0(BdrvDirtyBitmap, 1);
-    bitmap->bitmap = hbitmap_alloc(bitmap_size, ctz32(sector_granularity));
+    /*
+     * TODO - let hbitmap track full granularity. For now, it is tracking
+     * only sector granularity, as a shortcut for our iterators.
+     */
+    bitmap->bitmap = hbitmap_alloc(bitmap_size >> BDRV_SECTOR_BITS,
+                                   ctz32(granularity) - BDRV_SECTOR_BITS);
     bitmap->size = bitmap_size;
     bitmap->name = g_strdup(name);
     bitmap->disabled = false;
@@ -246,12 +248,13 @@ BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,
 void bdrv_dirty_bitmap_truncate(BlockDriverState *bs)
 {
     BdrvDirtyBitmap *bitmap;
-    uint64_t size = bdrv_nb_sectors(bs);
+    int64_t size = bdrv_getlength(bs);
 
+    assert(size >= 0);
     QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
         assert(!bdrv_dirty_bitmap_frozen(bitmap));
         assert(!bitmap->active_iterators);
-        hbitmap_truncate(bitmap->bitmap, size);
+        hbitmap_truncate(bitmap->bitmap, size >> BDRV_SECTOR_BITS);
         bitmap->size = size;
     }
 }
@@ -419,7 +422,7 @@ void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out)
         hbitmap_reset_all(bitmap->bitmap);
     } else {
         HBitmap *backup = bitmap->bitmap;
-        bitmap->bitmap = hbitmap_alloc(bitmap->size,
+        bitmap->bitmap = hbitmap_alloc(bitmap->size >> BDRV_SECTOR_BITS,
                                        hbitmap_granularity(backup));
         *out = backup;
     }
Signature · 1 line
2.9.3
Reviewed-by on v1 4/12
#13 lore raw

Re: [Qemu-devel] [PATCH 04/12] dirty-bitmap: Track size in bytes

Quoted 75 lines · Eric Blake

We are still using an internal hbitmap that tracks a size in sectors, with the granularity scaled down accordingly, because it lets us use a shortcut for our iterators which are currently sector-based. But there's no reason we can't track the dirty bitmap size in bytes, since it is an internal-only variable.

---
 block/dirty-bitmap.c | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)
block/dirty-bitmap.c +12 -9
index 32698d5..a413df1 100644
@@ -41,7 +41,7 @@ struct BdrvDirtyBitmap {
     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) */
+    int64_t size;               /* Size of the bitmap, in bytes */
     bool disabled;              /* Bitmap is read-only */
     int active_iterators;       /* How many iterators are active */
     QLIST_ENTRY(BdrvDirtyBitmap) list;
@@ -79,24 +79,26 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
 {
     int64_t bitmap_size;
     BdrvDirtyBitmap *bitmap;
-    uint32_t sector_granularity;
 
-    assert((granularity & (granularity - 1)) == 0);
+    assert(is_power_of_2(granularity) && granularity >= BDRV_SECTOR_SIZE);
 
     if (name && bdrv_find_dirty_bitmap(bs, name)) {
         error_setg(errp, "Bitmap already exists: %s", name);
         return NULL;
     }
-    sector_granularity = granularity >> BDRV_SECTOR_BITS;
-    assert(sector_granularity);
-    bitmap_size = bdrv_nb_sectors(bs);
+    bitmap_size = bdrv_getlength(bs);
     if (bitmap_size < 0) {
         error_setg_errno(errp, -bitmap_size, "could not get length of device");
         errno = -bitmap_size;
         return NULL;
     }
     bitmap = g_new0(BdrvDirtyBitmap, 1);
-    bitmap->bitmap = hbitmap_alloc(bitmap_size, ctz32(sector_granularity));
+    /*
+     * TODO - let hbitmap track full granularity. For now, it is tracking
+     * only sector granularity, as a shortcut for our iterators.
+     */
+    bitmap->bitmap = hbitmap_alloc(bitmap_size >> BDRV_SECTOR_BITS,
+                                   ctz32(granularity) - BDRV_SECTOR_BITS);
     bitmap->size = bitmap_size;
     bitmap->name = g_strdup(name);
     bitmap->disabled = false;
@@ -246,12 +248,13 @@ BdrvDirtyBitmap *bdrv_reclaim_dirty_bitmap(BlockDriverState *bs,
 void bdrv_dirty_bitmap_truncate(BlockDriverState *bs)
 {
     BdrvDirtyBitmap *bitmap;
-    uint64_t size = bdrv_nb_sectors(bs);
+    int64_t size = bdrv_getlength(bs);
 
+    assert(size >= 0);
     QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
         assert(!bdrv_dirty_bitmap_frozen(bitmap));
         assert(!bitmap->active_iterators);
-        hbitmap_truncate(bitmap->bitmap, size);
+        hbitmap_truncate(bitmap->bitmap, size >> BDRV_SECTOR_BITS);
         bitmap->size = size;
     }
 }

block/dirty-bitmap.c void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out) · line 428

Quoted 8 lines
block/dirty-bitmap.c +1 -1
@@ -419,7 +422,7 @@ void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out)
         hbitmap_reset_all(bitmap->bitmap);
     } else {
         HBitmap *backup = bitmap->bitmap;
-        bitmap->bitmap = hbitmap_alloc(bitmap->size,
+        bitmap->bitmap = hbitmap_alloc(bitmap->size >> BDRV_SECTOR_BITS,
                                        hbitmap_granularity(backup));
         *out = backup;
     }
author
#14 lore raw

PATCH 5/12 dirty-bitmap: Set iterator start by offset, not sector

In reply to Eric Blake

All callers to bdrv_dirty_iter_new() passed 0 for their initial starting point, drop that parameter.

All callers to bdrv_set_dirty_iter() were scaling an offset to a sector number; move the scaling to occur internally to dirty bitmap code instead.

---
 include/block/dirty-bitmap.h | 5 ++---
 block/backup.c               | 5 ++---
 block/dirty-bitmap.c         | 9 ++++-----
 block/mirror.c               | 4 ++--
 4 files changed, 10 insertions(+), 13 deletions(-)
include/block/dirty-bitmap.h +2 -3
index a83979d..efcec60 100644
@@ -41,11 +41,10 @@ void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
 void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
                              int64_t cur_sector, int64_t nr_sectors);
 BdrvDirtyBitmapIter *bdrv_dirty_meta_iter_new(BdrvDirtyBitmap *bitmap);
-BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap,
-                                         uint64_t first_sector);
+BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap);
 void bdrv_dirty_iter_free(BdrvDirtyBitmapIter *iter);
 int64_t bdrv_dirty_iter_next(BdrvDirtyBitmapIter *iter);
-void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *hbi, int64_t sector_num);
+void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *hbi, int64_t offset);
 int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap);
 int64_t bdrv_get_meta_dirty_count(BdrvDirtyBitmap *bitmap);
 void bdrv_dirty_bitmap_truncate(BlockDriverState *bs);
block/backup.c +2 -3
index 63ca208..efa4896 100644
@@ -372,7 +372,7 @@ static int coroutine_fn backup_run_incremental(BackupBlockJob *job)
 
     granularity = bdrv_dirty_bitmap_granularity(job->sync_bitmap);
     clusters_per_iter = MAX((granularity / job->cluster_size), 1);
-    dbi = bdrv_dirty_iter_new(job->sync_bitmap, 0);
+    dbi = bdrv_dirty_iter_new(job->sync_bitmap);
 
     /* Find the next dirty sector(s) */
     while ((offset = bdrv_dirty_iter_next(dbi) * BDRV_SECTOR_SIZE) >= 0) {
@@ -403,8 +403,7 @@ static int coroutine_fn backup_run_incremental(BackupBlockJob *job)
         /* If the bitmap granularity is smaller than the backup granularity,
          * we need to advance the iterator pointer to the next cluster. */
         if (granularity < job->cluster_size) {
-            bdrv_set_dirty_iter(dbi,
-                                cluster * job->cluster_size / BDRV_SECTOR_SIZE);
+            bdrv_set_dirty_iter(dbi, cluster * job->cluster_size);
         }
 
         last_cluster = cluster - 1;
block/dirty-bitmap.c +4 -5
index a413df1..3fb4871 100644
@@ -367,11 +367,10 @@ uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap)
     return BDRV_SECTOR_SIZE << hbitmap_granularity(bitmap->bitmap);
 }
 
-BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap,
-                                         uint64_t first_sector)
+BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap)
 {
     BdrvDirtyBitmapIter *iter = g_new(BdrvDirtyBitmapIter, 1);
-    hbitmap_iter_init(&iter->hbi, bitmap->bitmap, first_sector);
+    hbitmap_iter_init(&iter->hbi, bitmap->bitmap, 0);
     iter->bitmap = bitmap;
     bitmap->active_iterators++;
     return iter;
@@ -488,9 +487,9 @@ void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector,
 /**
  * Advance a BdrvDirtyBitmapIter to an arbitrary offset.
  */
-void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *iter, int64_t sector_num)
+void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *iter, int64_t offset)
 {
-    hbitmap_iter_init(&iter->hbi, iter->hbi.hb, sector_num);
+    hbitmap_iter_init(&iter->hbi, iter->hbi.hb, offset >> BDRV_SECTOR_BITS);
 }
 
 int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap)
block/mirror.c +2 -2
index c92335a..7c1d6bf 100644
@@ -370,7 +370,7 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
         next_dirty = bdrv_dirty_iter_next(s->dbi) * BDRV_SECTOR_SIZE;
         if (next_dirty > next_offset || next_dirty < 0) {
             /* The bitmap iterator's cache is stale, refresh it */
-            bdrv_set_dirty_iter(s->dbi, next_offset >> BDRV_SECTOR_BITS);
+            bdrv_set_dirty_iter(s->dbi, next_offset);
             next_dirty = bdrv_dirty_iter_next(s->dbi) * BDRV_SECTOR_SIZE;
         }
         assert(next_dirty == next_offset);
@@ -779,7 +779,7 @@ static void coroutine_fn mirror_run(void *opaque)
     }
 
     assert(!s->dbi);
-    s->dbi = bdrv_dirty_iter_new(s->dirty_bitmap, 0);
+    s->dbi = bdrv_dirty_iter_new(s->dirty_bitmap);
     for (;;) {
         uint64_t delay_ns = 0;
         int64_t cnt, delta;
Signature · 1 line
2.9.3
Reviewed-by on v1 5/12
#15 lore raw

Re: [Qemu-devel] [PATCH 05/12] dirty-bitmap: Set iterator start by offset, not sector

Quoted 101 lines · Eric Blake

All callers to bdrv_dirty_iter_new() passed 0 for their initial starting point, drop that parameter.

All callers to bdrv_set_dirty_iter() were scaling an offset to a sector number; move the scaling to occur internally to dirty bitmap code instead.

---
 include/block/dirty-bitmap.h | 5 ++---
 block/backup.c               | 5 ++---
 block/dirty-bitmap.c         | 9 ++++-----
 block/mirror.c               | 4 ++--
 4 files changed, 10 insertions(+), 13 deletions(-)
include/block/dirty-bitmap.h +2 -3
index a83979d..efcec60 100644
@@ -41,11 +41,10 @@ void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
 void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
                              int64_t cur_sector, int64_t nr_sectors);
 BdrvDirtyBitmapIter *bdrv_dirty_meta_iter_new(BdrvDirtyBitmap *bitmap);
-BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap,
-                                         uint64_t first_sector);
+BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap);
 void bdrv_dirty_iter_free(BdrvDirtyBitmapIter *iter);
 int64_t bdrv_dirty_iter_next(BdrvDirtyBitmapIter *iter);
-void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *hbi, int64_t sector_num);
+void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *hbi, int64_t offset);
 int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap);
 int64_t bdrv_get_meta_dirty_count(BdrvDirtyBitmap *bitmap);
 void bdrv_dirty_bitmap_truncate(BlockDriverState *bs);
block/backup.c +2 -3
index 63ca208..efa4896 100644
@@ -372,7 +372,7 @@ static int coroutine_fn backup_run_incremental(BackupBlockJob *job)
 
     granularity = bdrv_dirty_bitmap_granularity(job->sync_bitmap);
     clusters_per_iter = MAX((granularity / job->cluster_size), 1);
-    dbi = bdrv_dirty_iter_new(job->sync_bitmap, 0);
+    dbi = bdrv_dirty_iter_new(job->sync_bitmap);
 
     /* Find the next dirty sector(s) */
     while ((offset = bdrv_dirty_iter_next(dbi) * BDRV_SECTOR_SIZE) >= 0) {
@@ -403,8 +403,7 @@ static int coroutine_fn backup_run_incremental(BackupBlockJob *job)
         /* If the bitmap granularity is smaller than the backup granularity,
          * we need to advance the iterator pointer to the next cluster. */
         if (granularity < job->cluster_size) {
-            bdrv_set_dirty_iter(dbi,
-                                cluster * job->cluster_size / BDRV_SECTOR_SIZE);
+            bdrv_set_dirty_iter(dbi, cluster * job->cluster_size);
         }
 
         last_cluster = cluster - 1;
block/dirty-bitmap.c +4 -5
index a413df1..3fb4871 100644
@@ -367,11 +367,10 @@ uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap)
     return BDRV_SECTOR_SIZE << hbitmap_granularity(bitmap->bitmap);
 }
 
-BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap,
-                                         uint64_t first_sector)
+BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap)
 {
     BdrvDirtyBitmapIter *iter = g_new(BdrvDirtyBitmapIter, 1);
-    hbitmap_iter_init(&iter->hbi, bitmap->bitmap, first_sector);
+    hbitmap_iter_init(&iter->hbi, bitmap->bitmap, 0);
     iter->bitmap = bitmap;
     bitmap->active_iterators++;
     return iter;
@@ -488,9 +487,9 @@ void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector,
 /**
  * Advance a BdrvDirtyBitmapIter to an arbitrary offset.
  */
-void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *iter, int64_t sector_num)
+void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *iter, int64_t offset)
 {
-    hbitmap_iter_init(&iter->hbi, iter->hbi.hb, sector_num);
+    hbitmap_iter_init(&iter->hbi, iter->hbi.hb, offset >> BDRV_SECTOR_BITS);
 }
 
 int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap)
block/mirror.c +1 -1
index c92335a..7c1d6bf 100644
@@ -370,7 +370,7 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
         next_dirty = bdrv_dirty_iter_next(s->dbi) * BDRV_SECTOR_SIZE;
         if (next_dirty > next_offset || next_dirty < 0) {
             /* The bitmap iterator's cache is stale, refresh it */
-            bdrv_set_dirty_iter(s->dbi, next_offset >> BDRV_SECTOR_BITS);
+            bdrv_set_dirty_iter(s->dbi, next_offset);
             next_dirty = bdrv_dirty_iter_next(s->dbi) * BDRV_SECTOR_SIZE;
         }
         assert(next_dirty == next_offset);

block/mirror.c static void coroutine_fn mirror_run(void *opaque) · line 785

Quoted 8 lines
block/mirror.c +1 -1
@@ -779,7 +779,7 @@ static void coroutine_fn mirror_run(void *opaque)
     }
 
     assert(!s->dbi);
-    s->dbi = bdrv_dirty_iter_new(s->dirty_bitmap, 0);
+    s->dbi = bdrv_dirty_iter_new(s->dirty_bitmap);
     for (;;) {
         uint64_t delay_ns = 0;
         int64_t cnt, delta;
author
#16 lore raw

PATCH 6/12 dirty-bitmap: Change bdrv_dirty_iter_next() to report byte offset

In reply to Eric Blake

Thanks to recent cleanups, all callers were scaling a return value of sectors into bytes; do the scaling internally instead.

---
 block/backup.c       | 2 +-
 block/dirty-bitmap.c | 2 +-
 block/mirror.c       | 8 ++++----
 3 files changed, 6 insertions(+), 6 deletions(-)
block/backup.c +1 -1
index efa4896..6efd864 100644
@@ -375,7 +375,7 @@ static int coroutine_fn backup_run_incremental(BackupBlockJob *job)
     dbi = bdrv_dirty_iter_new(job->sync_bitmap);
 
     /* Find the next dirty sector(s) */
-    while ((offset = bdrv_dirty_iter_next(dbi) * BDRV_SECTOR_SIZE) >= 0) {
+    while ((offset = bdrv_dirty_iter_next(dbi)) >= 0) {
         cluster = offset / job->cluster_size;
 
         /* Fake progress updates for any clusters we skipped */
block/dirty-bitmap.c +1 -1
index 3fb4871..2f9f554 100644
@@ -397,7 +397,7 @@ void bdrv_dirty_iter_free(BdrvDirtyBitmapIter *iter)
 
 int64_t bdrv_dirty_iter_next(BdrvDirtyBitmapIter *iter)
 {
-    return hbitmap_iter_next(&iter->hbi);
+    return hbitmap_iter_next(&iter->hbi) * BDRV_SECTOR_SIZE;
 }
 
 void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
block/mirror.c +4 -4
index 7c1d6bf..f404ff3 100644
@@ -335,10 +335,10 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
     bool write_zeroes_ok = bdrv_can_write_zeroes_with_unmap(blk_bs(s->target));
     int max_io_bytes = MAX(s->buf_size / MAX_IN_FLIGHT, MAX_IO_BYTES);
 
-    offset = bdrv_dirty_iter_next(s->dbi) * BDRV_SECTOR_SIZE;
+    offset = bdrv_dirty_iter_next(s->dbi);
     if (offset < 0) {
         bdrv_set_dirty_iter(s->dbi, 0);
-        offset = bdrv_dirty_iter_next(s->dbi) * BDRV_SECTOR_SIZE;
+        offset = bdrv_dirty_iter_next(s->dbi);
         trace_mirror_restart_iter(s, bdrv_get_dirty_count(s->dirty_bitmap) *
                                   BDRV_SECTOR_SIZE);
         assert(offset >= 0);
@@ -367,11 +367,11 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
             break;
         }
 
-        next_dirty = bdrv_dirty_iter_next(s->dbi) * BDRV_SECTOR_SIZE;
+        next_dirty = bdrv_dirty_iter_next(s->dbi);
         if (next_dirty > next_offset || next_dirty < 0) {
             /* The bitmap iterator's cache is stale, refresh it */
             bdrv_set_dirty_iter(s->dbi, next_offset);
-            next_dirty = bdrv_dirty_iter_next(s->dbi) * BDRV_SECTOR_SIZE;
+            next_dirty = bdrv_dirty_iter_next(s->dbi);
         }
         assert(next_dirty == next_offset);
         nb_chunks++;
Signature · 1 line
2.9.3
Reviewed-by on v1 6/12
#17 lore raw

Re: [Qemu-devel] [PATCH 06/12] dirty-bitmap: Change bdrv_dirty_iter_next() to report byte offset

Quoted 58 lines · Eric Blake

Thanks to recent cleanups, all callers were scaling a return value of sectors into bytes; do the scaling internally instead.

---
 block/backup.c       | 2 +-
 block/dirty-bitmap.c | 2 +-
 block/mirror.c       | 8 ++++----
 3 files changed, 6 insertions(+), 6 deletions(-)
block/backup.c +1 -1
index efa4896..6efd864 100644
@@ -375,7 +375,7 @@ static int coroutine_fn backup_run_incremental(BackupBlockJob *job)
     dbi = bdrv_dirty_iter_new(job->sync_bitmap);
 
     /* Find the next dirty sector(s) */
-    while ((offset = bdrv_dirty_iter_next(dbi) * BDRV_SECTOR_SIZE) >= 0) {
+    while ((offset = bdrv_dirty_iter_next(dbi)) >= 0) {
         cluster = offset / job->cluster_size;
 
         /* Fake progress updates for any clusters we skipped */
block/dirty-bitmap.c +1 -1
index 3fb4871..2f9f554 100644
@@ -397,7 +397,7 @@ void bdrv_dirty_iter_free(BdrvDirtyBitmapIter *iter)
 
 int64_t bdrv_dirty_iter_next(BdrvDirtyBitmapIter *iter)
 {
-    return hbitmap_iter_next(&iter->hbi);
+    return hbitmap_iter_next(&iter->hbi) * BDRV_SECTOR_SIZE;
 }
 
 void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
block/mirror.c +2 -2
index 7c1d6bf..f404ff3 100644
@@ -335,10 +335,10 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
     bool write_zeroes_ok = bdrv_can_write_zeroes_with_unmap(blk_bs(s->target));
     int max_io_bytes = MAX(s->buf_size / MAX_IN_FLIGHT, MAX_IO_BYTES);
 
-    offset = bdrv_dirty_iter_next(s->dbi) * BDRV_SECTOR_SIZE;
+    offset = bdrv_dirty_iter_next(s->dbi);
     if (offset < 0) {
         bdrv_set_dirty_iter(s->dbi, 0);
-        offset = bdrv_dirty_iter_next(s->dbi) * BDRV_SECTOR_SIZE;
+        offset = bdrv_dirty_iter_next(s->dbi);
         trace_mirror_restart_iter(s, bdrv_get_dirty_count(s->dirty_bitmap) *
                                   BDRV_SECTOR_SIZE);
         assert(offset >= 0);
@@ -367,11 +367,11 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
             break;
         }
 

block/mirror.c static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s) · line 377

Quoted 10 lines
block/mirror.c +2 -2
-        next_dirty = bdrv_dirty_iter_next(s->dbi) * BDRV_SECTOR_SIZE;
+        next_dirty = bdrv_dirty_iter_next(s->dbi);
         if (next_dirty > next_offset || next_dirty < 0) {
             /* The bitmap iterator's cache is stale, refresh it */
             bdrv_set_dirty_iter(s->dbi, next_offset);
-            next_dirty = bdrv_dirty_iter_next(s->dbi) * BDRV_SECTOR_SIZE;
+            next_dirty = bdrv_dirty_iter_next(s->dbi);
         }
         assert(next_dirty == next_offset);
         nb_chunks++;
author
#18 lore raw

PATCH 7/12 dirty-bitmap: Change bdrv_get_dirty_count() to report bytes

In reply to Eric Blake

Thanks to recent cleanups, all callers were scaling a return value of sectors into bytes; do the scaling internally instead.

---
 block/dirty-bitmap.c |  4 ++--
 block/mirror.c       | 13 +++++--------
 migration/block.c    |  2 +-
 3 files changed, 8 insertions(+), 11 deletions(-)
block/dirty-bitmap.c +2 -2
index 2f9f554..e3c2e34 100644
@@ -319,7 +319,7 @@ BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
     QLIST_FOREACH(bm, &bs->dirty_bitmaps, list) {
         BlockDirtyInfo *info = g_new0(BlockDirtyInfo, 1);
         BlockDirtyInfoList *entry = g_new0(BlockDirtyInfoList, 1);
-        info->count = bdrv_get_dirty_count(bm) << BDRV_SECTOR_BITS;
+        info->count = bdrv_get_dirty_count(bm);
         info->granularity = bdrv_dirty_bitmap_granularity(bm);
         info->has_name = !!bm->name;
         info->name = g_strdup(bm->name);
@@ -494,7 +494,7 @@ void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *iter, int64_t offset)
 
 int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap)
 {
-    return hbitmap_count(bitmap->bitmap);
+    return hbitmap_count(bitmap->bitmap) << BDRV_SECTOR_BITS;
 }
 
 int64_t bdrv_get_meta_dirty_count(BdrvDirtyBitmap *bitmap)
block/mirror.c +5 -8
index f404ff3..1b98a77 100644
@@ -794,11 +794,10 @@ static void coroutine_fn mirror_run(void *opaque)
 
         cnt = bdrv_get_dirty_count(s->dirty_bitmap);
         /* s->common.offset contains the number of bytes already processed so
-         * far, cnt is the number of dirty sectors remaining and
+         * far, cnt is the number of dirty bytes remaining and
          * s->bytes_in_flight is the number of bytes currently being
          * processed; together those are the current total operation length */
-        s->common.len = s->common.offset + s->bytes_in_flight +
-            cnt * BDRV_SECTOR_SIZE;
+        s->common.len = s->common.offset + s->bytes_in_flight + cnt;
 
         /* Note that even when no rate limit is applied we need to yield
          * periodically with no pending I/O so that bdrv_drain_all() returns.
@@ -810,8 +809,7 @@ static void coroutine_fn mirror_run(void *opaque)
             s->common.iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
             if (s->in_flight >= MAX_IN_FLIGHT || s->buf_free_count == 0 ||
                 (cnt == 0 && s->in_flight > 0)) {
-                trace_mirror_yield(s, cnt * BDRV_SECTOR_SIZE,
-                                   s->buf_free_count, s->in_flight);
+                trace_mirror_yield(s, cnt, s->buf_free_count, s->in_flight);
                 mirror_wait_for_io(s);
                 continue;
             } else if (cnt != 0) {
@@ -852,7 +850,7 @@ static void coroutine_fn mirror_run(void *opaque)
              * whether to switch to target check one last time if I/O has
              * come in the meanwhile, and if not flush the data to disk.
              */
-            trace_mirror_before_drain(s, cnt * BDRV_SECTOR_SIZE);
+            trace_mirror_before_drain(s, cnt);
 
             bdrv_drained_begin(bs);
             cnt = bdrv_get_dirty_count(s->dirty_bitmap);
@@ -871,8 +869,7 @@ static void coroutine_fn mirror_run(void *opaque)
         }
 
         ret = 0;
-        trace_mirror_before_sleep(s, cnt * BDRV_SECTOR_SIZE,
-                                  s->synced, delay_ns);
+        trace_mirror_before_sleep(s, cnt, s->synced, delay_ns);
         if (!s->synced) {
             block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, delay_ns);
             if (block_job_is_cancelled(&s->common)) {
migration/block.c +1 -1
index 9a9c214..3daa5c7 100644
@@ -672,7 +672,7 @@ static int64_t get_remaining_dirty(void)
         aio_context_release(blk_get_aio_context(bmds->blk));
     }
 
-    return dirty << BDRV_SECTOR_BITS;
+    return dirty;
 }
 
 /* Called with iothread lock taken.  */
Signature · 1 line
2.9.3
Reviewed-by on v1 7/12
#19 lore raw

Re: [Qemu-devel] [PATCH 07/12] dirty-bitmap: Change bdrv_get_dirty_count() to report bytes

Quoted 85 lines · Eric Blake

Thanks to recent cleanups, all callers were scaling a return value of sectors into bytes; do the scaling internally instead.

---
 block/dirty-bitmap.c |  4 ++--
 block/mirror.c       | 13 +++++--------
 migration/block.c    |  2 +-
 3 files changed, 8 insertions(+), 11 deletions(-)
block/dirty-bitmap.c +2 -2
index 2f9f554..e3c2e34 100644
@@ -319,7 +319,7 @@ BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
     QLIST_FOREACH(bm, &bs->dirty_bitmaps, list) {
         BlockDirtyInfo *info = g_new0(BlockDirtyInfo, 1);
         BlockDirtyInfoList *entry = g_new0(BlockDirtyInfoList, 1);
-        info->count = bdrv_get_dirty_count(bm) << BDRV_SECTOR_BITS;
+        info->count = bdrv_get_dirty_count(bm);
         info->granularity = bdrv_dirty_bitmap_granularity(bm);
         info->has_name = !!bm->name;
         info->name = g_strdup(bm->name);
@@ -494,7 +494,7 @@ void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *iter, int64_t offset)
 
 int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap)
 {
-    return hbitmap_count(bitmap->bitmap);
+    return hbitmap_count(bitmap->bitmap) << BDRV_SECTOR_BITS;
 }
 
 int64_t bdrv_get_meta_dirty_count(BdrvDirtyBitmap *bitmap)
block/mirror.c +5 -8
index f404ff3..1b98a77 100644
@@ -794,11 +794,10 @@ static void coroutine_fn mirror_run(void *opaque)
 
         cnt = bdrv_get_dirty_count(s->dirty_bitmap);
         /* s->common.offset contains the number of bytes already processed so
-         * far, cnt is the number of dirty sectors remaining and
+         * far, cnt is the number of dirty bytes remaining and
          * s->bytes_in_flight is the number of bytes currently being
          * processed; together those are the current total operation length */
-        s->common.len = s->common.offset + s->bytes_in_flight +
-            cnt * BDRV_SECTOR_SIZE;
+        s->common.len = s->common.offset + s->bytes_in_flight + cnt;
 
         /* Note that even when no rate limit is applied we need to yield
          * periodically with no pending I/O so that bdrv_drain_all() returns.
@@ -810,8 +809,7 @@ static void coroutine_fn mirror_run(void *opaque)
             s->common.iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
             if (s->in_flight >= MAX_IN_FLIGHT || s->buf_free_count == 0 ||
                 (cnt == 0 && s->in_flight > 0)) {
-                trace_mirror_yield(s, cnt * BDRV_SECTOR_SIZE,
-                                   s->buf_free_count, s->in_flight);
+                trace_mirror_yield(s, cnt, s->buf_free_count, s->in_flight);
                 mirror_wait_for_io(s);
                 continue;
             } else if (cnt != 0) {
@@ -852,7 +850,7 @@ static void coroutine_fn mirror_run(void *opaque)
              * whether to switch to target check one last time if I/O has
              * come in the meanwhile, and if not flush the data to disk.
              */
-            trace_mirror_before_drain(s, cnt * BDRV_SECTOR_SIZE);
+            trace_mirror_before_drain(s, cnt);
 
             bdrv_drained_begin(bs);
             cnt = bdrv_get_dirty_count(s->dirty_bitmap);
@@ -871,8 +869,7 @@ static void coroutine_fn mirror_run(void *opaque)
         }
 
         ret = 0;
-        trace_mirror_before_sleep(s, cnt * BDRV_SECTOR_SIZE,
-                                  s->synced, delay_ns);
+        trace_mirror_before_sleep(s, cnt, s->synced, delay_ns);
         if (!s->synced) {
             block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, delay_ns);
             if (block_job_is_cancelled(&s->common)) {
migration/block.c +0 -0
index 9a9c214..3daa5c7 100644

migration/block.c static int64_t get_remaining_dirty(void) · line 678

Quoted 8 lines
migration/block.c +1 -1
@@ -672,7 +672,7 @@ static int64_t get_remaining_dirty(void)
         aio_context_release(blk_get_aio_context(bmds->blk));
     }
 
-    return dirty << BDRV_SECTOR_BITS;
+    return dirty;
 }
 
 /* Called with iothread lock taken.  */
Reviewed-by on v1 7/12
#20 lore raw

Re: [Qemu-devel] [PATCH 07/12] dirty-bitmap: Change bdrv_get_dirty_count() to report bytes

In reply to Eric Blake
Quoted 85 lines · Eric Blake

Thanks to recent cleanups, all callers were scaling a return value of sectors into bytes; do the scaling internally instead.

---
 block/dirty-bitmap.c |  4 ++--
 block/mirror.c       | 13 +++++--------
 migration/block.c    |  2 +-
 3 files changed, 8 insertions(+), 11 deletions(-)
block/dirty-bitmap.c +2 -2
index 2f9f554..e3c2e34 100644
@@ -319,7 +319,7 @@ BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
     QLIST_FOREACH(bm, &bs->dirty_bitmaps, list) {
         BlockDirtyInfo *info = g_new0(BlockDirtyInfo, 1);
         BlockDirtyInfoList *entry = g_new0(BlockDirtyInfoList, 1);
-        info->count = bdrv_get_dirty_count(bm) << BDRV_SECTOR_BITS;
+        info->count = bdrv_get_dirty_count(bm);
         info->granularity = bdrv_dirty_bitmap_granularity(bm);
         info->has_name = !!bm->name;
         info->name = g_strdup(bm->name);
@@ -494,7 +494,7 @@ void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *iter, int64_t offset)
 
 int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap)
 {
-    return hbitmap_count(bitmap->bitmap);
+    return hbitmap_count(bitmap->bitmap) << BDRV_SECTOR_BITS;
 }
 
 int64_t bdrv_get_meta_dirty_count(BdrvDirtyBitmap *bitmap)
block/mirror.c +5 -8
index f404ff3..1b98a77 100644
@@ -794,11 +794,10 @@ static void coroutine_fn mirror_run(void *opaque)
 
         cnt = bdrv_get_dirty_count(s->dirty_bitmap);
         /* s->common.offset contains the number of bytes already processed so
-         * far, cnt is the number of dirty sectors remaining and
+         * far, cnt is the number of dirty bytes remaining and
          * s->bytes_in_flight is the number of bytes currently being
          * processed; together those are the current total operation length */
-        s->common.len = s->common.offset + s->bytes_in_flight +
-            cnt * BDRV_SECTOR_SIZE;
+        s->common.len = s->common.offset + s->bytes_in_flight + cnt;
 
         /* Note that even when no rate limit is applied we need to yield
          * periodically with no pending I/O so that bdrv_drain_all() returns.
@@ -810,8 +809,7 @@ static void coroutine_fn mirror_run(void *opaque)
             s->common.iostatus == BLOCK_DEVICE_IO_STATUS_OK) {
             if (s->in_flight >= MAX_IN_FLIGHT || s->buf_free_count == 0 ||
                 (cnt == 0 && s->in_flight > 0)) {
-                trace_mirror_yield(s, cnt * BDRV_SECTOR_SIZE,
-                                   s->buf_free_count, s->in_flight);
+                trace_mirror_yield(s, cnt, s->buf_free_count, s->in_flight);
                 mirror_wait_for_io(s);
                 continue;
             } else if (cnt != 0) {
@@ -852,7 +850,7 @@ static void coroutine_fn mirror_run(void *opaque)
              * whether to switch to target check one last time if I/O has
              * come in the meanwhile, and if not flush the data to disk.
              */
-            trace_mirror_before_drain(s, cnt * BDRV_SECTOR_SIZE);
+            trace_mirror_before_drain(s, cnt);
 
             bdrv_drained_begin(bs);
             cnt = bdrv_get_dirty_count(s->dirty_bitmap);
@@ -871,8 +869,7 @@ static void coroutine_fn mirror_run(void *opaque)
         }
 
         ret = 0;
-        trace_mirror_before_sleep(s, cnt * BDRV_SECTOR_SIZE,
-                                  s->synced, delay_ns);
+        trace_mirror_before_sleep(s, cnt, s->synced, delay_ns);
         if (!s->synced) {
             block_job_sleep_ns(&s->common, QEMU_CLOCK_REALTIME, delay_ns);
             if (block_job_is_cancelled(&s->common)) {
migration/block.c +0 -0
index 9a9c214..3daa5c7 100644

migration/block.c static int64_t get_remaining_dirty(void) · line 678

Quoted 8 lines
migration/block.c +1 -1
@@ -672,7 +672,7 @@ static int64_t get_remaining_dirty(void)
         aio_context_release(blk_get_aio_context(bmds->blk));
     }
 
-    return dirty << BDRV_SECTOR_BITS;
+    return dirty;
 }
 
 /* Called with iothread lock taken.  */
author
#21 lore raw

PATCH 8/12 dirty-bitmap: Change bdrv_get_dirty() to take bytes

In reply to Eric Blake

Half the callers were already scaling bytes to sectors; the other half can eventually be simplified to use byte iteration. Both callers were already using the result as a bool, so make that explicit. Making the change also makes it easier for a future dirty-bitmap patch to offload scaling over to the internal hbitmap.

---
 include/block/dirty-bitmap.h | 4 ++--
 block/dirty-bitmap.c         | 8 ++++----
 block/mirror.c               | 3 +--
 migration/block.c            | 3 +--
 4 files changed, 8 insertions(+), 10 deletions(-)
include/block/dirty-bitmap.h +2 -2
index efcec60..b8434e5 100644
@@ -34,8 +34,8 @@ bool bdrv_dirty_bitmap_enabled(BdrvDirtyBitmap *bitmap);
 bool bdrv_dirty_bitmap_frozen(BdrvDirtyBitmap *bitmap);
 const char *bdrv_dirty_bitmap_name(const BdrvDirtyBitmap *bitmap);
 DirtyBitmapStatus bdrv_dirty_bitmap_status(BdrvDirtyBitmap *bitmap);
-int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
-                   int64_t sector);
+bool bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
+                    int64_t offset);
 void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
                            int64_t cur_sector, int64_t nr_sectors);
 void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
block/dirty-bitmap.c +4 -4
index e3c2e34..c8100d2 100644
@@ -332,13 +332,13 @@ BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
     return list;
 }
 
-int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
-                   int64_t sector)
+bool bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
+                    int64_t offset)
 {
     if (bitmap) {
-        return hbitmap_get(bitmap->bitmap, sector);
+        return hbitmap_get(bitmap->bitmap, offset >> BDRV_SECTOR_BITS);
     } else {
-        return 0;
+        return false;
     }
 }
 
block/mirror.c +1 -2
index 1b98a77..1e2e655 100644
@@ -359,8 +359,7 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
         int64_t next_offset = offset + nb_chunks * s->granularity;
         int64_t next_chunk = next_offset / s->granularity;
         if (next_offset >= s->bdev_length ||
-            !bdrv_get_dirty(source, s->dirty_bitmap,
-                            next_offset >> BDRV_SECTOR_BITS)) {
+            !bdrv_get_dirty(source, s->dirty_bitmap, next_offset)) {
             break;
         }
         if (test_bit(next_chunk, s->in_flight_bitmap)) {
migration/block.c +1 -2
index 3daa5c7..9e21aeb 100644
@@ -537,8 +537,7 @@ static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds,
         } else {
             blk_mig_unlock();
         }
-        if (bdrv_get_dirty(bs, bmds->dirty_bitmap, sector)) {
-
+        if (bdrv_get_dirty(bs, bmds->dirty_bitmap, sector * BDRV_SECTOR_SIZE)) {
             if (total_sectors - sector < BDRV_SECTORS_PER_DIRTY_CHUNK) {
                 nr_sectors = total_sectors - sector;
             } else {
Signature · 1 line
2.9.3
Reviewed-by on v1 8/12
#22 lore raw

Re: [Qemu-devel] [PATCH 08/12] dirty-bitmap: Change bdrv_get_dirty() to take bytes

Quoted 70 lines · Eric Blake

Half the callers were already scaling bytes to sectors; the other half can eventually be simplified to use byte iteration. Both callers were already using the result as a bool, so make that explicit. Making the change also makes it easier for a future dirty-bitmap patch to offload scaling over to the internal hbitmap.

---
 include/block/dirty-bitmap.h | 4 ++--
 block/dirty-bitmap.c         | 8 ++++----
 block/mirror.c               | 3 +--
 migration/block.c            | 3 +--
 4 files changed, 8 insertions(+), 10 deletions(-)
include/block/dirty-bitmap.h +2 -2
index efcec60..b8434e5 100644
@@ -34,8 +34,8 @@ bool bdrv_dirty_bitmap_enabled(BdrvDirtyBitmap *bitmap);
 bool bdrv_dirty_bitmap_frozen(BdrvDirtyBitmap *bitmap);
 const char *bdrv_dirty_bitmap_name(const BdrvDirtyBitmap *bitmap);
 DirtyBitmapStatus bdrv_dirty_bitmap_status(BdrvDirtyBitmap *bitmap);
-int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
-                   int64_t sector);
+bool bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
+                    int64_t offset);
 void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
                            int64_t cur_sector, int64_t nr_sectors);
 void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
block/dirty-bitmap.c +4 -4
index e3c2e34..c8100d2 100644
@@ -332,13 +332,13 @@ BlockDirtyInfoList *bdrv_query_dirty_bitmaps(BlockDriverState *bs)
     return list;
 }
 
-int bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
-                   int64_t sector)
+bool bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
+                    int64_t offset)
 {
     if (bitmap) {
-        return hbitmap_get(bitmap->bitmap, sector);
+        return hbitmap_get(bitmap->bitmap, offset >> BDRV_SECTOR_BITS);
     } else {
-        return 0;
+        return false;
     }
 }
 
block/mirror.c +1 -2
index 1b98a77..1e2e655 100644
@@ -359,8 +359,7 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
         int64_t next_offset = offset + nb_chunks * s->granularity;
         int64_t next_chunk = next_offset / s->granularity;
         if (next_offset >= s->bdev_length ||
-            !bdrv_get_dirty(source, s->dirty_bitmap,
-                            next_offset >> BDRV_SECTOR_BITS)) {
+            !bdrv_get_dirty(source, s->dirty_bitmap, next_offset)) {
             break;
         }
         if (test_bit(next_chunk, s->in_flight_bitmap)) {
migration/block.c +0 -0
index 3daa5c7..9e21aeb 100644

migration/block.c static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds, · line 540

Quoted 6 lines
migration/block.c +1 -2
@@ -537,8 +537,7 @@ static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds,
         } else {
             blk_mig_unlock();
         }
-        if (bdrv_get_dirty(bs, bmds->dirty_bitmap, sector)) {
-
+        if (bdrv_get_dirty(bs, bmds->dirty_bitmap, sector * BDRV_SECTOR_SIZE)) {

This one is a little weirder now though, isn't it? We're asking for the dirty status of a single byte, technically. In practice, the scaling factor will always cover the entire sector, but it reads a lot jankier now.

migration/block.c static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds, · line 543

Quoted 4 lines
migration/block.c +0 -0
             if (total_sectors - sector < BDRV_SECTORS_PER_DIRTY_CHUNK) {
                 nr_sectors = total_sectors - sector;
             } else {

Oh well, it was always janky...

author
#23 lore raw

Re: [Qemu-devel] [PATCH 08/12] dirty-bitmap: Change bdrv_get_dirty() to take bytes

Quoted 13 lines · John Snow

migration/block.c static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds, · line 540

Quoted 8 lines

+++ b/migration/block.c

migration/block.c +1 -2
@@ -537,8 +537,7 @@ static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds,
         } else {
             blk_mig_unlock();
         }
-        if (bdrv_get_dirty(bs, bmds->dirty_bitmap, sector)) {
-
+        if (bdrv_get_dirty(bs, bmds->dirty_bitmap, sector * BDRV_SECTOR_SIZE)) {

This one is a little weirder now though, isn't it? We're asking for the dirty status of a single byte, technically. In practice, the scaling factor will always cover the entire sector, but it reads a lot jankier now.

Quoted 6 lines

migration/block.c static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds, · line 543

Quoted 4 lines
migration/block.c +0 -0
             if (total_sectors - sector < BDRV_SECTORS_PER_DIRTY_CHUNK) {
                 nr_sectors = total_sectors - sector;
             } else {

Oh well, it was always janky...

True. Think of it as "is the granularity (which may be a sector, a cluster, or even some other size) that contains 'offset' dirty?". I really think migration/block.c will be easier to read once converted to byte operations everywhere, but have not yet tackled it (it was hard enough tackling mirror, backup, commit, and stream in parallel for the previous series).

Quoted 3 lines

Thanks for the reviews, by the way, even if the prerequisite patches still haven't been fully reviewed.

Signature · 3 lines
Eric Blake, Principal Software Engineer
Red Hat, Inc.           +1-919-301-3266
Virtualization:  qemu.org | libvirt.org
author
#24 lore raw

PATCH 9/12 dirty-bitmap: Change bdrv_[re]set_dirty_bitmap() to use bytes

In reply to Eric Blake

Some of the callers were already scaling bytes to sectors; others can be easily converted to pass byte offsets, all in our shift towards a consistent byte interface everywhere. Making the change will also make it easier to write the hold-out callers to use byte rather than sectors for their iterations; it also makes it easier for a future dirty-bitmap patch to offload scaling over to the internal hbitmap. Although all callers happen to pass sector-aligned values, make the internal scaling robust to any sub-sector requests.

---
 include/block/dirty-bitmap.h |  4 ++--
 block/dirty-bitmap.c         | 14 ++++++++++----
 block/mirror.c               | 16 ++++++++--------
 migration/block.c            |  7 +++++--
 4 files changed, 25 insertions(+), 16 deletions(-)
include/block/dirty-bitmap.h +2 -2
index b8434e5..fdff1e2 100644
@@ -37,9 +37,9 @@ DirtyBitmapStatus bdrv_dirty_bitmap_status(BdrvDirtyBitmap *bitmap);
 bool bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
                     int64_t offset);
 void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
-                           int64_t cur_sector, int64_t nr_sectors);
+                           int64_t offset, int64_t bytes);
 void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
-                             int64_t cur_sector, int64_t nr_sectors);
+                             int64_t offset, int64_t bytes);
 BdrvDirtyBitmapIter *bdrv_dirty_meta_iter_new(BdrvDirtyBitmap *bitmap);
 BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap);
 void bdrv_dirty_iter_free(BdrvDirtyBitmapIter *iter);
block/dirty-bitmap.c +10 -4
index c8100d2..8e7822c 100644
@@ -401,17 +401,23 @@ int64_t bdrv_dirty_iter_next(BdrvDirtyBitmapIter *iter)
 }
 
 void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
-                           int64_t cur_sector, int64_t nr_sectors)
+                           int64_t offset, int64_t bytes)
 {
+    int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE);
+
     assert(bdrv_dirty_bitmap_enabled(bitmap));
-    hbitmap_set(bitmap->bitmap, cur_sector, nr_sectors);
+    hbitmap_set(bitmap->bitmap, offset >> BDRV_SECTOR_BITS,
+                end_sector - (offset >> BDRV_SECTOR_BITS));
 }
 
 void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
-                             int64_t cur_sector, int64_t nr_sectors)
+                             int64_t offset, int64_t bytes)
 {
+    int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE);
+
     assert(bdrv_dirty_bitmap_enabled(bitmap));
-    hbitmap_reset(bitmap->bitmap, cur_sector, nr_sectors);
+    hbitmap_reset(bitmap->bitmap, offset >> BDRV_SECTOR_BITS,
+                  end_sector - (offset >> BDRV_SECTOR_BITS));
 }
 
 void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out)
block/mirror.c +8 -8
index 1e2e655..21b4f5d 100644
@@ -141,8 +141,7 @@ static void mirror_write_complete(void *opaque, int ret)
     if (ret < 0) {
         BlockErrorAction action;
 
-        bdrv_set_dirty_bitmap(s->dirty_bitmap, op->offset >> BDRV_SECTOR_BITS,
-                              op->bytes >> BDRV_SECTOR_BITS);
+        bdrv_set_dirty_bitmap(s->dirty_bitmap, op->offset, op->bytes);
         action = mirror_error_action(s, false, -ret);
         if (action == BLOCK_ERROR_ACTION_REPORT && s->ret >= 0) {
             s->ret = ret;
@@ -161,8 +160,7 @@ static void mirror_read_complete(void *opaque, int ret)
     if (ret < 0) {
         BlockErrorAction action;
 
-        bdrv_set_dirty_bitmap(s->dirty_bitmap, op->offset >> BDRV_SECTOR_BITS,
-                              op->bytes >> BDRV_SECTOR_BITS);
+        bdrv_set_dirty_bitmap(s->dirty_bitmap, op->offset, op->bytes);
         action = mirror_error_action(s, true, -ret);
         if (action == BLOCK_ERROR_ACTION_REPORT && s->ret >= 0) {
             s->ret = ret;
@@ -380,8 +378,8 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
      * calling bdrv_get_block_status_above could yield - if some blocks are
      * marked dirty in this window, we need to know.
      */
-    bdrv_reset_dirty_bitmap(s->dirty_bitmap, offset >> BDRV_SECTOR_BITS,
-                            nb_chunks * sectors_per_chunk);
+    bdrv_reset_dirty_bitmap(s->dirty_bitmap, offset,
+                            nb_chunks * s->granularity);
     bitmap_set(s->in_flight_bitmap, offset / s->granularity, nb_chunks);
     while (nb_chunks > 0 && offset < s->bdev_length) {
         int64_t ret;
@@ -614,7 +612,7 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s)
 
     if (base == NULL && !bdrv_has_zero_init(target_bs)) {
         if (!bdrv_can_write_zeroes_with_unmap(target_bs)) {
-            bdrv_set_dirty_bitmap(s->dirty_bitmap, 0, end);
+            bdrv_set_dirty_bitmap(s->dirty_bitmap, 0, s->bdev_length);
             return 0;
         }
 
@@ -667,7 +665,9 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s)
         n = DIV_ROUND_UP(count, BDRV_SECTOR_SIZE);
         assert(n > 0);
         if (ret == 1) {
-            bdrv_set_dirty_bitmap(s->dirty_bitmap, sector_num, n);
+            bdrv_set_dirty_bitmap(s->dirty_bitmap,
+                                  sector_num * BDRV_SECTOR_SIZE,
+                                  n * BDRV_SECTOR_SIZE);
         }
         sector_num += n;
     }
migration/block.c +5 -2
index 9e21aeb..e875211 100644
@@ -331,7 +331,8 @@ static int mig_save_device_bulk(QEMUFile *f, BlkMigDevState *bmds)
     blk->aiocb = blk_aio_preadv(bb, cur_sector * BDRV_SECTOR_SIZE, &blk->qiov,
                                 0, blk_mig_read_cb, blk);
 
-    bdrv_reset_dirty_bitmap(bmds->dirty_bitmap, cur_sector, nr_sectors);
+    bdrv_reset_dirty_bitmap(bmds->dirty_bitmap, cur_sector * BDRV_SECTOR_SIZE,
+                            nr_sectors * BDRV_SECTOR_SIZE);
     aio_context_release(blk_get_aio_context(bmds->blk));
     qemu_mutex_unlock_iothread();
 
@@ -575,7 +576,9 @@ static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds,
                 g_free(blk);
             }
 
-            bdrv_reset_dirty_bitmap(bmds->dirty_bitmap, sector, nr_sectors);
+            bdrv_reset_dirty_bitmap(bmds->dirty_bitmap,
+                                    sector * BDRV_SECTOR_SIZE,
+                                    nr_sectors * BDRV_SECTOR_SIZE);
             sector += nr_sectors;
             bmds->cur_dirty = sector;
 
Signature · 1 line
2.9.3
Reviewed-by on v1 9/12
#25 lore raw

Re: [Qemu-devel] [PATCH 09/12] dirty-bitmap: Change bdrv_[re]set_dirty_bitmap() to use bytes

Quoted 136 lines · Eric Blake

Some of the callers were already scaling bytes to sectors; others can be easily converted to pass byte offsets, all in our shift towards a consistent byte interface everywhere. Making the change will also make it easier to write the hold-out callers to use byte rather than sectors for their iterations; it also makes it easier for a future dirty-bitmap patch to offload scaling over to the internal hbitmap. Although all callers happen to pass sector-aligned values, make the internal scaling robust to any sub-sector requests.

---
 include/block/dirty-bitmap.h |  4 ++--
 block/dirty-bitmap.c         | 14 ++++++++++----
 block/mirror.c               | 16 ++++++++--------
 migration/block.c            |  7 +++++--
 4 files changed, 25 insertions(+), 16 deletions(-)
include/block/dirty-bitmap.h +2 -2
index b8434e5..fdff1e2 100644
@@ -37,9 +37,9 @@ DirtyBitmapStatus bdrv_dirty_bitmap_status(BdrvDirtyBitmap *bitmap);
 bool bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
                     int64_t offset);
 void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
-                           int64_t cur_sector, int64_t nr_sectors);
+                           int64_t offset, int64_t bytes);
 void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
-                             int64_t cur_sector, int64_t nr_sectors);
+                             int64_t offset, int64_t bytes);
 BdrvDirtyBitmapIter *bdrv_dirty_meta_iter_new(BdrvDirtyBitmap *bitmap);
 BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap);
 void bdrv_dirty_iter_free(BdrvDirtyBitmapIter *iter);
block/dirty-bitmap.c +10 -4
index c8100d2..8e7822c 100644
@@ -401,17 +401,23 @@ int64_t bdrv_dirty_iter_next(BdrvDirtyBitmapIter *iter)
 }
 
 void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
-                           int64_t cur_sector, int64_t nr_sectors)
+                           int64_t offset, int64_t bytes)
 {
+    int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE);
+
     assert(bdrv_dirty_bitmap_enabled(bitmap));
-    hbitmap_set(bitmap->bitmap, cur_sector, nr_sectors);
+    hbitmap_set(bitmap->bitmap, offset >> BDRV_SECTOR_BITS,
+                end_sector - (offset >> BDRV_SECTOR_BITS));
 }
 
 void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
-                             int64_t cur_sector, int64_t nr_sectors)
+                             int64_t offset, int64_t bytes)
 {
+    int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE);
+
     assert(bdrv_dirty_bitmap_enabled(bitmap));
-    hbitmap_reset(bitmap->bitmap, cur_sector, nr_sectors);
+    hbitmap_reset(bitmap->bitmap, offset >> BDRV_SECTOR_BITS,
+                  end_sector - (offset >> BDRV_SECTOR_BITS));
 }
 
 void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out)
block/mirror.c +8 -8
index 1e2e655..21b4f5d 100644
@@ -141,8 +141,7 @@ static void mirror_write_complete(void *opaque, int ret)
     if (ret < 0) {
         BlockErrorAction action;
 
-        bdrv_set_dirty_bitmap(s->dirty_bitmap, op->offset >> BDRV_SECTOR_BITS,
-                              op->bytes >> BDRV_SECTOR_BITS);
+        bdrv_set_dirty_bitmap(s->dirty_bitmap, op->offset, op->bytes);
         action = mirror_error_action(s, false, -ret);
         if (action == BLOCK_ERROR_ACTION_REPORT && s->ret >= 0) {
             s->ret = ret;
@@ -161,8 +160,7 @@ static void mirror_read_complete(void *opaque, int ret)
     if (ret < 0) {
         BlockErrorAction action;
 
-        bdrv_set_dirty_bitmap(s->dirty_bitmap, op->offset >> BDRV_SECTOR_BITS,
-                              op->bytes >> BDRV_SECTOR_BITS);
+        bdrv_set_dirty_bitmap(s->dirty_bitmap, op->offset, op->bytes);
         action = mirror_error_action(s, true, -ret);
         if (action == BLOCK_ERROR_ACTION_REPORT && s->ret >= 0) {
             s->ret = ret;
@@ -380,8 +378,8 @@ static uint64_t coroutine_fn mirror_iteration(MirrorBlockJob *s)
      * calling bdrv_get_block_status_above could yield - if some blocks are
      * marked dirty in this window, we need to know.
      */
-    bdrv_reset_dirty_bitmap(s->dirty_bitmap, offset >> BDRV_SECTOR_BITS,
-                            nb_chunks * sectors_per_chunk);
+    bdrv_reset_dirty_bitmap(s->dirty_bitmap, offset,
+                            nb_chunks * s->granularity);
     bitmap_set(s->in_flight_bitmap, offset / s->granularity, nb_chunks);
     while (nb_chunks > 0 && offset < s->bdev_length) {
         int64_t ret;
@@ -614,7 +612,7 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s)
 
     if (base == NULL && !bdrv_has_zero_init(target_bs)) {
         if (!bdrv_can_write_zeroes_with_unmap(target_bs)) {
-            bdrv_set_dirty_bitmap(s->dirty_bitmap, 0, end);
+            bdrv_set_dirty_bitmap(s->dirty_bitmap, 0, s->bdev_length);
             return 0;
         }
 
@@ -667,7 +665,9 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s)
         n = DIV_ROUND_UP(count, BDRV_SECTOR_SIZE);
         assert(n > 0);
         if (ret == 1) {
-            bdrv_set_dirty_bitmap(s->dirty_bitmap, sector_num, n);
+            bdrv_set_dirty_bitmap(s->dirty_bitmap,
+                                  sector_num * BDRV_SECTOR_SIZE,
+                                  n * BDRV_SECTOR_SIZE);
         }
         sector_num += n;
     }
migration/block.c +2 -1
index 9e21aeb..e875211 100644
@@ -331,7 +331,8 @@ static int mig_save_device_bulk(QEMUFile *f, BlkMigDevState *bmds)
     blk->aiocb = blk_aio_preadv(bb, cur_sector * BDRV_SECTOR_SIZE, &blk->qiov,
                                 0, blk_mig_read_cb, blk);
 
-    bdrv_reset_dirty_bitmap(bmds->dirty_bitmap, cur_sector, nr_sectors);
+    bdrv_reset_dirty_bitmap(bmds->dirty_bitmap, cur_sector * BDRV_SECTOR_SIZE,
+                            nr_sectors * BDRV_SECTOR_SIZE);
     aio_context_release(blk_get_aio_context(bmds->blk));
     qemu_mutex_unlock_iothread();
 

migration/block.c static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds, · line 584

Quoted 10 lines
migration/block.c +3 -1
@@ -575,7 +576,9 @@ static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds,
                 g_free(blk);
             }
 
-            bdrv_reset_dirty_bitmap(bmds->dirty_bitmap, sector, nr_sectors);
+            bdrv_reset_dirty_bitmap(bmds->dirty_bitmap,
+                                    sector * BDRV_SECTOR_SIZE,
+                                    nr_sectors * BDRV_SECTOR_SIZE);
             sector += nr_sectors;
             bmds->cur_dirty = sector;
 
author
#26 lore raw

PATCH 10/12 mirror: Switch mirror_dirty_init() to byte-based iteration

In reply to Eric Blake

Now that we have adjusted the majority of the calls this function makes to be byte-based, it is easier to read the code if it makes passes over the image using bytes rather than sectors.

---
 block/mirror.c | 35 ++++++++++++++---------------------
 1 file changed, 14 insertions(+), 21 deletions(-)
block/mirror.c +14 -21
index 21b4f5d..846e392 100644
@@ -601,15 +601,13 @@ static void mirror_throttle(MirrorBlockJob *s)
 
 static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s)
 {
-    int64_t sector_num, end;
+    int64_t offset;
     BlockDriverState *base = s->base;
     BlockDriverState *bs = s->source;
     BlockDriverState *target_bs = blk_bs(s->target);
-    int ret, n;
+    int ret;
     int64_t count;
 
-    end = s->bdev_length / BDRV_SECTOR_SIZE;
-
     if (base == NULL && !bdrv_has_zero_init(target_bs)) {
         if (!bdrv_can_write_zeroes_with_unmap(target_bs)) {
             bdrv_set_dirty_bitmap(s->dirty_bitmap, 0, s->bdev_length);
@@ -617,9 +615,9 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s)
         }
 
         s->initial_zeroing_ongoing = true;
-        for (sector_num = 0; sector_num < end; ) {
-            int nb_sectors = MIN(end - sector_num,
-                QEMU_ALIGN_DOWN(INT_MAX, s->granularity) >> BDRV_SECTOR_BITS);
+        for (offset = 0; offset < s->bdev_length; ) {
+            int bytes = MIN(s->bdev_length - offset,
+                            QEMU_ALIGN_DOWN(INT_MAX, s->granularity));
 
             mirror_throttle(s);
 
@@ -635,9 +633,8 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s)
                 continue;
             }
 
-            mirror_do_zero_or_discard(s, sector_num * BDRV_SECTOR_SIZE,
-                                      nb_sectors * BDRV_SECTOR_SIZE, false);
-            sector_num += nb_sectors;
+            mirror_do_zero_or_discard(s, offset, bytes, false);
+            offset += bytes;
         }
 
         mirror_wait_for_all_io(s);
@@ -645,10 +642,10 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s)
     }
 
     /* First part, loop on the sectors and initialize the dirty bitmap.  */
-    for (sector_num = 0; sector_num < end; ) {
+    for (offset = 0; offset < s->bdev_length; ) {
         /* Just to make sure we are not exceeding int limit. */
-        int nb_sectors = MIN(INT_MAX >> BDRV_SECTOR_BITS,
-                             end - sector_num);
+        int bytes = MIN(s->bdev_length - offset,
+                        QEMU_ALIGN_DOWN(INT_MAX, s->granularity));
 
         mirror_throttle(s);
 
@@ -656,20 +653,16 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s)
             return 0;
         }
 
-        ret = bdrv_is_allocated_above(bs, base, sector_num * BDRV_SECTOR_SIZE,
-                                      nb_sectors * BDRV_SECTOR_SIZE, &count);
+        ret = bdrv_is_allocated_above(bs, base, offset, bytes, &count);
         if (ret < 0) {
             return ret;
         }
 
-        n = DIV_ROUND_UP(count, BDRV_SECTOR_SIZE);
-        assert(n > 0);
+        count = QEMU_ALIGN_UP(count, BDRV_SECTOR_SIZE);
         if (ret == 1) {
-            bdrv_set_dirty_bitmap(s->dirty_bitmap,
-                                  sector_num * BDRV_SECTOR_SIZE,
-                                  n * BDRV_SECTOR_SIZE);
+            bdrv_set_dirty_bitmap(s->dirty_bitmap, offset, count);
         }
-        sector_num += n;
+        offset += count;
     }
     return 0;
 }
Signature · 1 line
2.9.3
Reviewed-by on v1 10/12
#27 lore raw

Re: [Qemu-devel] [PATCH 10/12] mirror: Switch mirror_dirty_init() to byte-based iteration

Quoted 86 lines · Eric Blake

Now that we have adjusted the majority of the calls this function makes to be byte-based, it is easier to read the code if it makes passes over the image using bytes rather than sectors.

---
 block/mirror.c | 35 ++++++++++++++---------------------
 1 file changed, 14 insertions(+), 21 deletions(-)
block/mirror.c +12 -17
index 21b4f5d..846e392 100644
@@ -601,15 +601,13 @@ static void mirror_throttle(MirrorBlockJob *s)
 
 static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s)
 {
-    int64_t sector_num, end;
+    int64_t offset;
     BlockDriverState *base = s->base;
     BlockDriverState *bs = s->source;
     BlockDriverState *target_bs = blk_bs(s->target);
-    int ret, n;
+    int ret;
     int64_t count;
 
-    end = s->bdev_length / BDRV_SECTOR_SIZE;
-
     if (base == NULL && !bdrv_has_zero_init(target_bs)) {
         if (!bdrv_can_write_zeroes_with_unmap(target_bs)) {
             bdrv_set_dirty_bitmap(s->dirty_bitmap, 0, s->bdev_length);
@@ -617,9 +615,9 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s)
         }
 
         s->initial_zeroing_ongoing = true;
-        for (sector_num = 0; sector_num < end; ) {
-            int nb_sectors = MIN(end - sector_num,
-                QEMU_ALIGN_DOWN(INT_MAX, s->granularity) >> BDRV_SECTOR_BITS);
+        for (offset = 0; offset < s->bdev_length; ) {
+            int bytes = MIN(s->bdev_length - offset,
+                            QEMU_ALIGN_DOWN(INT_MAX, s->granularity));
 
             mirror_throttle(s);
 
@@ -635,9 +633,8 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s)
                 continue;
             }
 
-            mirror_do_zero_or_discard(s, sector_num * BDRV_SECTOR_SIZE,
-                                      nb_sectors * BDRV_SECTOR_SIZE, false);
-            sector_num += nb_sectors;
+            mirror_do_zero_or_discard(s, offset, bytes, false);
+            offset += bytes;
         }
 
         mirror_wait_for_all_io(s);
@@ -645,10 +642,10 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s)
     }
 
     /* First part, loop on the sectors and initialize the dirty bitmap.  */
-    for (sector_num = 0; sector_num < end; ) {
+    for (offset = 0; offset < s->bdev_length; ) {
         /* Just to make sure we are not exceeding int limit. */
-        int nb_sectors = MIN(INT_MAX >> BDRV_SECTOR_BITS,
-                             end - sector_num);
+        int bytes = MIN(s->bdev_length - offset,
+                        QEMU_ALIGN_DOWN(INT_MAX, s->granularity));
 
         mirror_throttle(s);
 
@@ -656,20 +653,16 @@ static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s)
             return 0;
         }
 
-        ret = bdrv_is_allocated_above(bs, base, sector_num * BDRV_SECTOR_SIZE,
-                                      nb_sectors * BDRV_SECTOR_SIZE, &count);
+        ret = bdrv_is_allocated_above(bs, base, offset, bytes, &count);
         if (ret < 0) {
             return ret;
         }
 
-        n = DIV_ROUND_UP(count, BDRV_SECTOR_SIZE);
-        assert(n > 0);
+        count = QEMU_ALIGN_UP(count, BDRV_SECTOR_SIZE);
         if (ret == 1) {

block/mirror.c static int coroutine_fn mirror_dirty_init(MirrorBlockJob *s) · line 668

Quoted 10 lines
block/mirror.c +2 -4
-            bdrv_set_dirty_bitmap(s->dirty_bitmap,
-                                  sector_num * BDRV_SECTOR_SIZE,
-                                  n * BDRV_SECTOR_SIZE);
+            bdrv_set_dirty_bitmap(s->dirty_bitmap, offset, count);
         }
-        sector_num += n;
+        offset += count;
     }
     return 0;
 }
author
#28 lore raw

PATCH 11/12 dirty-bitmap: Switch bdrv_set_dirty() to bytes

In reply to Eric Blake

Both callers already had bytes available, but were scaling to sectors. Move the scaling to internal code. In the case of bdrv_aligned_pwritev(), we are now passing the exact offset rather than a rounded sector-aligned value, but that's okay as long as dirty bitmap widens start/bytes to granularity boundaries.

---
 include/block/block_int.h | 2 +-
 block/dirty-bitmap.c      | 8 +++++---
 block/io.c                | 6 ++----
 3 files changed, 8 insertions(+), 8 deletions(-)
include/block/block_int.h +1 -1
index 08063c1..0b737fd 100644
@@ -917,7 +917,7 @@ void blk_dev_eject_request(BlockBackend *blk, bool force);
 bool blk_dev_is_tray_open(BlockBackend *blk);
 bool blk_dev_is_medium_locked(BlockBackend *blk);
 
-void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, int64_t nr_sect);
+void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes);
 bool bdrv_requests_pending(BlockDriverState *bs);
 
 void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out);
block/dirty-bitmap.c +5 -3
index 8e7822c..ef165eb 100644
@@ -478,15 +478,17 @@ void bdrv_dirty_bitmap_deserialize_finish(BdrvDirtyBitmap *bitmap)
     hbitmap_deserialize_finish(bitmap->bitmap);
 }
 
-void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector,
-                    int64_t nr_sectors)
+void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
     BdrvDirtyBitmap *bitmap;
+    int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE);
+
     QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
         if (!bdrv_dirty_bitmap_enabled(bitmap)) {
             continue;
         }
-        hbitmap_set(bitmap->bitmap, cur_sector, nr_sectors);
+        hbitmap_set(bitmap->bitmap, offset >> BDRV_SECTOR_BITS,
+                    end_sector - (offset >> BDRV_SECTOR_BITS));
     }
 }
 
block/io.c +2 -4
index 9218329..d22d35f 100644
@@ -1328,7 +1328,6 @@ static int coroutine_fn bdrv_aligned_pwritev(BdrvChild *child,
     bool waited;
     int ret;
 
-    int64_t start_sector = offset >> BDRV_SECTOR_BITS;
     int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE);
     uint64_t bytes_remaining = bytes;
     int max_transfer;
@@ -1407,7 +1406,7 @@ static int coroutine_fn bdrv_aligned_pwritev(BdrvChild *child,
     bdrv_debug_event(bs, BLKDBG_PWRITEV_DONE);
 
     ++bs->write_gen;
-    bdrv_set_dirty(bs, start_sector, end_sector - start_sector);
+    bdrv_set_dirty(bs, offset, bytes);
 
     if (bs->wr_highest_offset < offset + bytes) {
         bs->wr_highest_offset = offset + bytes;
@@ -2535,8 +2534,7 @@ int coroutine_fn bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset,
     ret = 0;
 out:
     ++bs->write_gen;
-    bdrv_set_dirty(bs, req.offset >> BDRV_SECTOR_BITS,
-                   req.bytes >> BDRV_SECTOR_BITS);
+    bdrv_set_dirty(bs, req.offset, req.bytes);
     tracked_request_end(&req);
     bdrv_dec_in_flight(bs);
     return ret;
Signature · 1 line
2.9.3
Reviewed-by on v1 11/12
#29 lore raw

Re: [Qemu-devel] [PATCH 11/12] dirty-bitmap: Switch bdrv_set_dirty() to bytes

Quoted 6 lines · Eric Blake

Both callers already had bytes available, but were scaling to sectors. Move the scaling to internal code. In the case of bdrv_aligned_pwritev(), we are now passing the exact offset rather than a rounded sector-aligned value, but that's okay as long as dirty bitmap widens start/bytes to granularity boundaries.

Yes, that shouldn't be a problem. Granularity math will make sure this comes out in the wash.

Quoted 33 lines
---
 include/block/block_int.h | 2 +-
 block/dirty-bitmap.c      | 8 +++++---
 block/io.c                | 6 ++----
 3 files changed, 8 insertions(+), 8 deletions(-)
include/block/block_int.h +1 -1
index 08063c1..0b737fd 100644
@@ -917,7 +917,7 @@ void blk_dev_eject_request(BlockBackend *blk, bool force);
 bool blk_dev_is_tray_open(BlockBackend *blk);
 bool blk_dev_is_medium_locked(BlockBackend *blk);
 
-void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector, int64_t nr_sect);
+void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes);
 bool bdrv_requests_pending(BlockDriverState *bs);
 
 void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out);
block/dirty-bitmap.c +1 -2
index 8e7822c..ef165eb 100644
@@ -478,15 +478,17 @@ void bdrv_dirty_bitmap_deserialize_finish(BdrvDirtyBitmap *bitmap)
     hbitmap_deserialize_finish(bitmap->bitmap);
 }
 
-void bdrv_set_dirty(BlockDriverState *bs, int64_t cur_sector,
-                    int64_t nr_sectors)
+void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {

block/dirty-bitmap.c void bdrv_dirty_bitmap_deserialize_finish(BdrvDirtyBitmap *bitmap) · line 491

Quoted 10 lines
block/dirty-bitmap.c +4 -1
     BdrvDirtyBitmap *bitmap;
+    int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE);
+
     QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
         if (!bdrv_dirty_bitmap_enabled(bitmap)) {
             continue;
         }
-        hbitmap_set(bitmap->bitmap, cur_sector, nr_sectors);
+        hbitmap_set(bitmap->bitmap, offset >> BDRV_SECTOR_BITS,
+                    end_sector - (offset >> BDRV_SECTOR_BITS));

Well, that's worse, but luckily you've got more patches. :)

Quoted 26 lines
block/dirty-bitmap.c +0 -0
     }
 }
 
block/io.c +1 -2
index 9218329..d22d35f 100644
@@ -1328,7 +1328,6 @@ static int coroutine_fn bdrv_aligned_pwritev(BdrvChild *child,
     bool waited;
     int ret;
 
-    int64_t start_sector = offset >> BDRV_SECTOR_BITS;
     int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE);
     uint64_t bytes_remaining = bytes;
     int max_transfer;
@@ -1407,7 +1406,7 @@ static int coroutine_fn bdrv_aligned_pwritev(BdrvChild *child,
     bdrv_debug_event(bs, BLKDBG_PWRITEV_DONE);
 
     ++bs->write_gen;
-    bdrv_set_dirty(bs, start_sector, end_sector - start_sector);
+    bdrv_set_dirty(bs, offset, bytes);
 
     if (bs->wr_highest_offset < offset + bytes) {
         bs->wr_highest_offset = offset + bytes;

block/io.c int coroutine_fn bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset, · line 2540

Quoted 9 lines
block/io.c +1 -2
@@ -2535,8 +2534,7 @@ int coroutine_fn bdrv_co_pdiscard(BlockDriverState *bs, int64_t offset,
     ret = 0;
 out:
     ++bs->write_gen;
-    bdrv_set_dirty(bs, req.offset >> BDRV_SECTOR_BITS,
-                   req.bytes >> BDRV_SECTOR_BITS);
+    bdrv_set_dirty(bs, req.offset, req.bytes);
     tracked_request_end(&req);
     bdrv_dec_in_flight(bs);
     return ret;
author
#30 lore raw

PATCH 12/12 dirty-bitmap: Convert internal hbitmap size/granularity

In reply to Eric Blake

Now that all callers are using byte-based interfaces, there's no reason for our internal hbitmap to remain with sector-based granularity. It also simplifies our internal scaling, since we already know that hbitmap widens requests out to granularity boundaries.

---
 block/dirty-bitmap.c | 37 ++++++++++++-------------------------
 1 file changed, 12 insertions(+), 25 deletions(-)
block/dirty-bitmap.c +12 -25
index ef165eb..26ca084 100644
@@ -37,7 +37,7 @@
  *     or enabled. A frozen bitmap can only abdicate() or reclaim().
  */
 struct BdrvDirtyBitmap {
-    HBitmap *bitmap;            /* Dirty sector bitmap implementation */
+    HBitmap *bitmap;            /* Dirty bitmap implementation */
     HBitmap *meta;              /* Meta dirty bitmap */
     BdrvDirtyBitmap *successor; /* Anonymous child; implies frozen status */
     char *name;                 /* Optional non-empty unique ID */
@@ -93,12 +93,7 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
         return NULL;
     }
     bitmap = g_new0(BdrvDirtyBitmap, 1);
-    /*
-     * TODO - let hbitmap track full granularity. For now, it is tracking
-     * only sector granularity, as a shortcut for our iterators.
-     */
-    bitmap->bitmap = hbitmap_alloc(bitmap_size >> BDRV_SECTOR_BITS,
-                                   ctz32(granularity) - BDRV_SECTOR_BITS);
+    bitmap->bitmap = hbitmap_alloc(bitmap_size, ctz32(granularity));
     bitmap->size = bitmap_size;
     bitmap->name = g_strdup(name);
     bitmap->disabled = false;
@@ -254,7 +249,7 @@ void bdrv_dirty_bitmap_truncate(BlockDriverState *bs)
     QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
         assert(!bdrv_dirty_bitmap_frozen(bitmap));
         assert(!bitmap->active_iterators);
-        hbitmap_truncate(bitmap->bitmap, size >> BDRV_SECTOR_BITS);
+        hbitmap_truncate(bitmap->bitmap, size);
         bitmap->size = size;
     }
 }
@@ -336,7 +331,7 @@ bool bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
                     int64_t offset)
 {
     if (bitmap) {
-        return hbitmap_get(bitmap->bitmap, offset >> BDRV_SECTOR_BITS);
+        return hbitmap_get(bitmap->bitmap, offset);
     } else {
         return false;
     }
@@ -364,7 +359,7 @@ uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs)
 
 uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap)
 {
-    return BDRV_SECTOR_SIZE << hbitmap_granularity(bitmap->bitmap);
+    return 1U << hbitmap_granularity(bitmap->bitmap);
 }
 
 BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap)
@@ -397,27 +392,21 @@ void bdrv_dirty_iter_free(BdrvDirtyBitmapIter *iter)
 
 int64_t bdrv_dirty_iter_next(BdrvDirtyBitmapIter *iter)
 {
-    return hbitmap_iter_next(&iter->hbi) * BDRV_SECTOR_SIZE;
+    return hbitmap_iter_next(&iter->hbi);
 }
 
 void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
                            int64_t offset, int64_t bytes)
 {
-    int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE);
-
     assert(bdrv_dirty_bitmap_enabled(bitmap));
-    hbitmap_set(bitmap->bitmap, offset >> BDRV_SECTOR_BITS,
-                end_sector - (offset >> BDRV_SECTOR_BITS));
+    hbitmap_set(bitmap->bitmap, offset, bytes);
 }
 
 void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
                              int64_t offset, int64_t bytes)
 {
-    int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE);
-
     assert(bdrv_dirty_bitmap_enabled(bitmap));
-    hbitmap_reset(bitmap->bitmap, offset >> BDRV_SECTOR_BITS,
-                  end_sector - (offset >> BDRV_SECTOR_BITS));
+    hbitmap_reset(bitmap->bitmap, offset, bytes);
 }
 
 void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out)
@@ -427,7 +416,7 @@ void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out)
         hbitmap_reset_all(bitmap->bitmap);
     } else {
         HBitmap *backup = bitmap->bitmap;
-        bitmap->bitmap = hbitmap_alloc(bitmap->size >> BDRV_SECTOR_BITS,
+        bitmap->bitmap = hbitmap_alloc(bitmap->size,
                                        hbitmap_granularity(backup));
         *out = backup;
     }
@@ -481,14 +470,12 @@ void bdrv_dirty_bitmap_deserialize_finish(BdrvDirtyBitmap *bitmap)
 void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
     BdrvDirtyBitmap *bitmap;
-    int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE);
 
     QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
         if (!bdrv_dirty_bitmap_enabled(bitmap)) {
             continue;
         }
-        hbitmap_set(bitmap->bitmap, offset >> BDRV_SECTOR_BITS,
-                    end_sector - (offset >> BDRV_SECTOR_BITS));
+        hbitmap_set(bitmap->bitmap, offset, bytes);
     }
 }
 
@@ -497,12 +484,12 @@ void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes)
  */
 void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *iter, int64_t offset)
 {
-    hbitmap_iter_init(&iter->hbi, iter->hbi.hb, offset >> BDRV_SECTOR_BITS);
+    hbitmap_iter_init(&iter->hbi, iter->hbi.hb, offset);
 }
 
 int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap)
 {
-    return hbitmap_count(bitmap->bitmap) << BDRV_SECTOR_BITS;
+    return hbitmap_count(bitmap->bitmap);
 }
 
 int64_t bdrv_get_meta_dirty_count(BdrvDirtyBitmap *bitmap)
Signature · 1 line
2.9.3
Reviewed-by on v1 12/12
#31 lore raw

Re: [Qemu-devel] [PATCH 12/12] dirty-bitmap: Convert internal hbitmap size/granularity

Quoted 127 lines · Eric Blake

Now that all callers are using byte-based interfaces, there's no reason for our internal hbitmap to remain with sector-based granularity. It also simplifies our internal scaling, since we already know that hbitmap widens requests out to granularity boundaries.

---
 block/dirty-bitmap.c | 37 ++++++++++++-------------------------
 1 file changed, 12 insertions(+), 25 deletions(-)
block/dirty-bitmap.c +10 -24
index ef165eb..26ca084 100644
@@ -37,7 +37,7 @@
  *     or enabled. A frozen bitmap can only abdicate() or reclaim().
  */
 struct BdrvDirtyBitmap {
-    HBitmap *bitmap;            /* Dirty sector bitmap implementation */
+    HBitmap *bitmap;            /* Dirty bitmap implementation */
     HBitmap *meta;              /* Meta dirty bitmap */
     BdrvDirtyBitmap *successor; /* Anonymous child; implies frozen status */
     char *name;                 /* Optional non-empty unique ID */
@@ -93,12 +93,7 @@ BdrvDirtyBitmap *bdrv_create_dirty_bitmap(BlockDriverState *bs,
         return NULL;
     }
     bitmap = g_new0(BdrvDirtyBitmap, 1);
-    /*
-     * TODO - let hbitmap track full granularity. For now, it is tracking
-     * only sector granularity, as a shortcut for our iterators.
-     */
-    bitmap->bitmap = hbitmap_alloc(bitmap_size >> BDRV_SECTOR_BITS,
-                                   ctz32(granularity) - BDRV_SECTOR_BITS);
+    bitmap->bitmap = hbitmap_alloc(bitmap_size, ctz32(granularity));
     bitmap->size = bitmap_size;
     bitmap->name = g_strdup(name);
     bitmap->disabled = false;
@@ -254,7 +249,7 @@ void bdrv_dirty_bitmap_truncate(BlockDriverState *bs)
     QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
         assert(!bdrv_dirty_bitmap_frozen(bitmap));
         assert(!bitmap->active_iterators);
-        hbitmap_truncate(bitmap->bitmap, size >> BDRV_SECTOR_BITS);
+        hbitmap_truncate(bitmap->bitmap, size);
         bitmap->size = size;
     }
 }
@@ -336,7 +331,7 @@ bool bdrv_get_dirty(BlockDriverState *bs, BdrvDirtyBitmap *bitmap,
                     int64_t offset)
 {
     if (bitmap) {
-        return hbitmap_get(bitmap->bitmap, offset >> BDRV_SECTOR_BITS);
+        return hbitmap_get(bitmap->bitmap, offset);
     } else {
         return false;
     }
@@ -364,7 +359,7 @@ uint32_t bdrv_get_default_bitmap_granularity(BlockDriverState *bs)
 
 uint32_t bdrv_dirty_bitmap_granularity(BdrvDirtyBitmap *bitmap)
 {
-    return BDRV_SECTOR_SIZE << hbitmap_granularity(bitmap->bitmap);
+    return 1U << hbitmap_granularity(bitmap->bitmap);
 }
 
 BdrvDirtyBitmapIter *bdrv_dirty_iter_new(BdrvDirtyBitmap *bitmap)
@@ -397,27 +392,21 @@ void bdrv_dirty_iter_free(BdrvDirtyBitmapIter *iter)
 
 int64_t bdrv_dirty_iter_next(BdrvDirtyBitmapIter *iter)
 {
-    return hbitmap_iter_next(&iter->hbi) * BDRV_SECTOR_SIZE;
+    return hbitmap_iter_next(&iter->hbi);
 }
 
 void bdrv_set_dirty_bitmap(BdrvDirtyBitmap *bitmap,
                            int64_t offset, int64_t bytes)
 {
-    int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE);
-
     assert(bdrv_dirty_bitmap_enabled(bitmap));
-    hbitmap_set(bitmap->bitmap, offset >> BDRV_SECTOR_BITS,
-                end_sector - (offset >> BDRV_SECTOR_BITS));
+    hbitmap_set(bitmap->bitmap, offset, bytes);
 }
 
 void bdrv_reset_dirty_bitmap(BdrvDirtyBitmap *bitmap,
                              int64_t offset, int64_t bytes)
 {
-    int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE);
-
     assert(bdrv_dirty_bitmap_enabled(bitmap));
-    hbitmap_reset(bitmap->bitmap, offset >> BDRV_SECTOR_BITS,
-                  end_sector - (offset >> BDRV_SECTOR_BITS));
+    hbitmap_reset(bitmap->bitmap, offset, bytes);
 }
 
 void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out)
@@ -427,7 +416,7 @@ void bdrv_clear_dirty_bitmap(BdrvDirtyBitmap *bitmap, HBitmap **out)
         hbitmap_reset_all(bitmap->bitmap);
     } else {
         HBitmap *backup = bitmap->bitmap;
-        bitmap->bitmap = hbitmap_alloc(bitmap->size >> BDRV_SECTOR_BITS,
+        bitmap->bitmap = hbitmap_alloc(bitmap->size,
                                        hbitmap_granularity(backup));
         *out = backup;
     }
@@ -481,14 +470,12 @@ void bdrv_dirty_bitmap_deserialize_finish(BdrvDirtyBitmap *bitmap)
 void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes)
 {
     BdrvDirtyBitmap *bitmap;
-    int64_t end_sector = DIV_ROUND_UP(offset + bytes, BDRV_SECTOR_SIZE);
 
     QLIST_FOREACH(bitmap, &bs->dirty_bitmaps, list) {
         if (!bdrv_dirty_bitmap_enabled(bitmap)) {
             continue;
         }
-        hbitmap_set(bitmap->bitmap, offset >> BDRV_SECTOR_BITS,
-                    end_sector - (offset >> BDRV_SECTOR_BITS));
+        hbitmap_set(bitmap->bitmap, offset, bytes);
     }
 }
 
@@ -497,12 +484,12 @@ void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes)
  */
 void bdrv_set_dirty_iter(BdrvDirtyBitmapIter *iter, int64_t offset)
 {
-    hbitmap_iter_init(&iter->hbi, iter->hbi.hb, offset >> BDRV_SECTOR_BITS);

block/dirty-bitmap.c void bdrv_set_dirty(BlockDriverState *bs, int64_t offset, int64_t bytes) · line 495

Quoted 10 lines
block/dirty-bitmap.c +2 -1
+    hbitmap_iter_init(&iter->hbi, iter->hbi.hb, offset);
 }
 
 int64_t bdrv_get_dirty_count(BdrvDirtyBitmap *bitmap)
 {
-    return hbitmap_count(bitmap->bitmap) << BDRV_SECTOR_BITS;
+    return hbitmap_count(bitmap->bitmap);
 }
 
 int64_t bdrv_get_meta_dirty_count(BdrvDirtyBitmap *bitmap)