hbitmap: fix hbitmap_status() return value for first dirty bit case

The last return statement should return true, as we already evaluated that
start == next_dirty

Also, fix hbitmap_status() descrip

hbitmap: fix hbitmap_status() return value for first dirty bit case

The last return statement should return true, as we already evaluated that
start == next_dirty

Also, fix hbitmap_status() description in header

Cc: qemu-stable@nongnu.org
Fixes: a6426475a75 ("block/dirty-bitmap: introduce bdrv_dirty_bitmap_status()")
Signed-off-by: Andrey Zhadchenko <andrey.zhadchenko@virtuozzo.com>
Message-Id: <20230202181523.423131-1-andrey.zhadchenko@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

hbitmap: fix hbitmap_status() return value for first dirty bit case

The last return statement should return true, as we already evaluated that
start == next_dirty

Also, fix hbitmap_status() descrip

hbitmap: fix hbitmap_status() return value for first dirty bit case

The last return statement should return true, as we already evaluated that
start == next_dirty

Also, fix hbitmap_status() description in header

Cc: qemu-stable@nongnu.org
Fixes: a6426475a75 ("block/dirty-bitmap: introduce bdrv_dirty_bitmap_status()")
Signed-off-by: Andrey Zhadchenko <andrey.zhadchenko@virtuozzo.com>
Message-Id: <20230202181523.423131-1-andrey.zhadchenko@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

show more ...

hbitmap: fix hbitmap_status() return value for first dirty bit case

The last return statement should return true, as we already evaluated that
start == next_dirty

Also, fix hbitmap_status() descrip

hbitmap: fix hbitmap_status() return value for first dirty bit case

The last return statement should return true, as we already evaluated that
start == next_dirty

Also, fix hbitmap_status() description in header

Cc: qemu-stable@nongnu.org
Fixes: a6426475a75 ("block/dirty-bitmap: introduce bdrv_dirty_bitmap_status()")
Signed-off-by: Andrey Zhadchenko <andrey.zhadchenko@virtuozzo.com>
Message-Id: <20230202181523.423131-1-andrey.zhadchenko@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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block: simplify handling of try to merge different sized bitmaps

We have too much logic to simply check that bitmaps are of the same
size. Let's just define that hbitmap_merge() and
bdrv_dirty_bitma

block: simplify handling of try to merge different sized bitmaps

We have too much logic to simply check that bitmaps are of the same
size. Let's just define that hbitmap_merge() and
bdrv_dirty_bitmap_merge_internal() require their argument bitmaps be of
same size, this simplifies things.

Let's look through the callers:

For backup_init_bcs_bitmap() we already assert that merge can't fail.

In bdrv_reclaim_dirty_bitmap_locked() we gracefully handle the error
that can't happen: successor always has same size as its parent, drop
this logic.

In bdrv_merge_dirty_bitmap() we already has assertion and separate
check. Make the check explicit and improve error message.

Signed-off-by: Vladimir Sementsov-Ogievskiy <v.sementsov-og@mail.ru>
Reviewed-by: Nikita Lapshin <nikita.lapshin@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20220517111206.23585-4-v.sementsov-og@mail.ru>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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block: simplify handling of try to merge different sized bitmaps

We have too much logic to simply check that bitmaps are of the same
size. Let's just define that hbitmap_merge() and
bdrv_dirty_bitma

block: simplify handling of try to merge different sized bitmaps

We have too much logic to simply check that bitmaps are of the same
size. Let's just define that hbitmap_merge() and
bdrv_dirty_bitmap_merge_internal() require their argument bitmaps be of
same size, this simplifies things.

Let's look through the callers:

For backup_init_bcs_bitmap() we already assert that merge can't fail.

In bdrv_reclaim_dirty_bitmap_locked() we gracefully handle the error
that can't happen: successor always has same size as its parent, drop
this logic.

In bdrv_merge_dirty_bitmap() we already has assertion and separate
check. Make the check explicit and improve error message.

Signed-off-by: Vladimir Sementsov-Ogievskiy <v.sementsov-og@mail.ru>
Reviewed-by: Nikita Lapshin <nikita.lapshin@virtuozzo.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20220517111206.23585-4-v.sementsov-og@mail.ru>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

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Use g_new() & friends where that makes obvious sense

g_new(T, n) is neater than g_malloc(sizeof(T) * n). It's also safer,
for two reasons. One, it catches multiplication overflowing size_t.
Two, i

Use g_new() & friends where that makes obvious sense

g_new(T, n) is neater than g_malloc(sizeof(T) * n). It's also safer,
for two reasons. One, it catches multiplication overflowing size_t.
Two, it returns T * rather than void *, which lets the compiler catch
more type errors.

This commit only touches allocations with size arguments of the form
sizeof(T).

Patch created mechanically with:

$ spatch --in-place --sp-file scripts/coccinelle/use-g_new-etc.cocci \
--macro-file scripts/cocci-macro-file.h FILES...

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Acked-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20220315144156.1595462-4-armbru@redhat.com>
Reviewed-by: Pavel Dovgalyuk <Pavel.Dovgalyuk@ispras.ru>

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block/dirty-bitmap: introduce bdrv_dirty_bitmap_status()

Add a convenient function similar with bdrv_block_status() to get
status of dirty bitmap.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vseme

block/dirty-bitmap: introduce bdrv_dirty_bitmap_status()

Add a convenient function similar with bdrv_block_status() to get
status of dirty bitmap.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Hanna Reitz <hreitz@redhat.com>
Message-Id: <20220303194349.2304213-9-vsementsov@virtuozzo.com>
Signed-off-by: Hanna Reitz <hreitz@redhat.com>

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block/dirty-bitmap: improve _next_dirty_area API

Firstly, _next_dirty_area is for scenarios when we may contiguously
search for next dirty area inside some limited region, so it is more
comfortable

block/dirty-bitmap: improve _next_dirty_area API

Firstly, _next_dirty_area is for scenarios when we may contiguously
search for next dirty area inside some limited region, so it is more
comfortable to specify "end" which should not be recalculated on each
iteration.

Secondly, let's add a possibility to limit resulting area size, not
limiting searching area. This will be used in NBD code in further
commit. (Note that now bdrv_dirty_bitmap_next_dirty_area is unused)

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20200205112041.6003-8-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>

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block/dirty-bitmap: add _next_dirty API

We have bdrv_dirty_bitmap_next_zero, let's add corresponding
bdrv_dirty_bitmap_next_dirty, which is more comfortable to use than
bitmap iterators in some case

block/dirty-bitmap: add _next_dirty API

We have bdrv_dirty_bitmap_next_zero, let's add corresponding
bdrv_dirty_bitmap_next_dirty, which is more comfortable to use than
bitmap iterators in some cases.

For test modify test_hbitmap_next_zero_check_range to check both
next_zero and next_dirty and add some new checks.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20200205112041.6003-7-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>

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block/dirty-bitmap: switch _next_dirty_area and _next_zero to int64_t

We are going to introduce bdrv_dirty_bitmap_next_dirty so that same
variable may be used to store its return value and to be its

block/dirty-bitmap: switch _next_dirty_area and _next_zero to int64_t

We are going to introduce bdrv_dirty_bitmap_next_dirty so that same
variable may be used to store its return value and to be its parameter,
so it would int64_t.

Similarly, we are going to refactor hbitmap_next_dirty_area to use
hbitmap_next_dirty together with hbitmap_next_zero, therefore we want
hbitmap_next_zero parameter type to be int64_t too.

So, for convenience update all parameters of *_next_zero and
*_next_dirty_area to be int64_t.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20200205112041.6003-6-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>

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hbitmap: drop meta bitmaps as they are unused

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.c

hbitmap: drop meta bitmaps as they are unused

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20200205112041.6003-5-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>

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hbitmap: unpublish hbitmap_iter_skip_words

Function is internal and even commented as internal. Drop its
definition from .h file.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.c

hbitmap: unpublish hbitmap_iter_skip_words

Function is internal and even commented as internal. Drop its
definition from .h file.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20200205112041.6003-4-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>

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hbitmap: move hbitmap_iter_next_word to hbitmap.c

The function is definitely internal (it's not used by third party and
it has complicated interface). Move it to .c file.

Signed-off-by: Vladimir Se

hbitmap: move hbitmap_iter_next_word to hbitmap.c

The function is definitely internal (it's not used by third party and
it has complicated interface). Move it to .c file.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20200205112041.6003-3-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>

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hbitmap: assert that we don't create bitmap larger than INT64_MAX

We have APIs which returns signed int64_t, to be able to return error.
Therefore we can't handle bitmaps with absolute size larger t

hbitmap: assert that we don't create bitmap larger than INT64_MAX

We have APIs which returns signed int64_t, to be able to return error.
Therefore we can't handle bitmaps with absolute size larger than
(INT64_MAX+1). Still, keep maximum to be INT64_MAX which is a bit
safer.

Note, that bitmaps are used to represent disk images, which can't
exceed INT64_MAX anyway.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20200205112041.6003-2-vsementsov@virtuozzo.com
Signed-off-by: John Snow <jsnow@redhat.com>

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hbitmap: handle set/reset with zero length

Passing zero length to these functions leads to unpredicted results.
Zero-length set/reset may occur in active-mirror, on zero-length write
(which is unlik

hbitmap: handle set/reset with zero length

Passing zero length to these functions leads to unpredicted results.
Zero-length set/reset may occur in active-mirror, on zero-length write
(which is unlikely, but not guaranteed to never happen).

Let's just do nothing on zero-length request.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20191011090711.19940-2-vsementsov@virtuozzo.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>

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util/hbitmap: strict hbitmap_reset

hbitmap_reset has an unobvious property: it rounds requested region up.
It may provoke bugs, like in recently fixed write-blocking mode of
mirror: user calls reset

util/hbitmap: strict hbitmap_reset

hbitmap_reset has an unobvious property: it rounds requested region up.
It may provoke bugs, like in recently fixed write-blocking mode of
mirror: user calls reset on unaligned region, not keeping in mind that
there are possible unrelated dirty bytes, covered by rounded-up region
and information of this unrelated "dirtiness" will be lost.

Make hbitmap_reset strict: assert that arguments are aligned, allowing
only one exception when @start + @count == hb->orig_size. It's needed
to comfort users of hbitmap_next_dirty_area, which cares about
hb->orig_size.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-Id: <20190806152611.280389-1-vsementsov@virtuozzo.com>
[Maintainer edit: Max's suggestions from on-list. --js]
[Maintainer edit: Eric's suggestion for aligned macro. --js]
Signed-off-by: John Snow <jsnow@redhat.com>

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hbitmap: enable merging across granularities

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-9-jsnow@redhat.com
Signed-off-by:

hbitmap: enable merging across granularities

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-9-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>

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hbitmap: Fix merge when b is empty, and result is not an alias of a

Nobody calls the function like this currently, but we neither prohibit
or cope with this behavior. I decided to make the function

hbitmap: Fix merge when b is empty, and result is not an alias of a

Nobody calls the function like this currently, but we neither prohibit
or cope with this behavior. I decided to make the function cope with it.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20190709232550.10724-8-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>

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util/hbitmap: update orig_size on truncate

Without this, hbitmap_next_zero and hbitmap_next_dirty_area are broken
after truncate. So, orig_size is broken since it's introduction in
76d570dc495c56bb.

util/hbitmap: update orig_size on truncate

Without this, hbitmap_next_zero and hbitmap_next_dirty_area are broken
after truncate. So, orig_size is broken since it's introduction in
76d570dc495c56bb.

Fixes: 76d570dc495c56bb
Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20190805120120.23585-1-vsementsov@virtuozzo.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Cc: qemu-stable@nongnu.org
Signed-off-by: Max Reitz <mreitz@redhat.com>

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Revert "hbitmap: Add @advance param to hbitmap_iter_next()"

This reverts commit a33fbb4f8b64226becf502a123733776ce319b24.

The functionality is unused.

Note: in addition to automatic revert, drop s

Revert "hbitmap: Add @advance param to hbitmap_iter_next()"

This reverts commit a33fbb4f8b64226becf502a123733776ce319b24.

The functionality is unused.

Note: in addition to automatic revert, drop second parameter in
hbitmap_iter_next() call from hbitmap_next_dirty_area() too.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>

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dirty-bitmap: add bdrv_dirty_bitmap_next_dirty_area

The function alters bdrv_dirty_iter_next_area(), which is wrong and
less efficient (see further commit
"block/mirror: fix and improve do_sync_targ

dirty-bitmap: add bdrv_dirty_bitmap_next_dirty_area

The function alters bdrv_dirty_iter_next_area(), which is wrong and
less efficient (see further commit
"block/mirror: fix and improve do_sync_target_write" for description).

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

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dirty-bitmap: improve bdrv_dirty_bitmap_next_zero

Add bytes parameter to the function, to limit searched range.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>

bitmap: Update count after a merge

We need an accurate count of the number of bits set in a bitmap
after a merge. In particular, since the merge operation short-circuits
a merge from an empty source

bitmap: Update count after a merge

We need an accurate count of the number of bits set in a bitmap
after a merge. In particular, since the merge operation short-circuits
a merge from an empty source, if you have bitmaps A, B, and C where
B started empty, then merge C into B, and B into A, an inaccurate
count meant that A did not get the contents of C.

In the worst case, we may falsely regard the bitmap as empty when
it has had new writes merged into it.

Fixes: be58721db
CC: qemu-stable@nongnu.org
Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-id: 20181002233314.30159-1-jsnow@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>

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dirty-bitmap: make it possible to restore bitmap after merge

Add backup parameter to bdrv_merge_dirty_bitmap() to be used then with
bdrv_restore_dirty_bitmap() if it needed to restore the bitmap aft

dirty-bitmap: make it possible to restore bitmap after merge

Add backup parameter to bdrv_merge_dirty_bitmap() to be used then with
bdrv_restore_dirty_bitmap() if it needed to restore the bitmap after
merge operation.

This is needed to implement bitmap merge transaction action in further
commit.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: John Snow <jsnow@redhat.com>

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hbitmap: Add @advance param to hbitmap_iter_next()

This new parameter allows the caller to just query the next dirty
position without moving the iterator.

Signed-off-by: Max Reitz <mreitz@redhat.co

hbitmap: Add @advance param to hbitmap_iter_next()

This new parameter allows the caller to just query the next dirty
position without moving the iterator.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Message-id: 20180613181823.13618-8-mreitz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>

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