off-by: Alberto Garcia
---
block/qcow2.c | 40 +---
1 file changed, 17 insertions(+), 23 deletions(-)
diff --git a/block/qcow2.c b/block/qcow2.c
index da56b1a4df..eeb125c697 100644
--- a/block/qcow2.c
+++ b/block/qcow2.c
@@ -2102,7 +2102,6 @@ static coroutine_fn
On Fri 04 Sep 2020 11:28:18 AM CEST, Max Reitz wrote:
>> + * If any clusters or subclusters were allocated then @m contains a
>> + * list with the information of all the affected regions. Note that
>> + * this can happen regardless of whether this function succeeds or
>> + * not. The caller is
be
reproduced with the included test case.
Signed-off-by: Alberto Garcia
---
block/qcow2-cluster.c | 3 --
tests/qemu-iotests/305 | 74 ++
tests/qemu-iotests/305.out | 16 +
tests/qemu-iotests/group | 1 +
4 files changed, 91 insertions(+), 3
the case, l2meta (nowadays a pointer to a list) is
only allocated when needed and nb_clusters is guaranteed to be > 0 so
this check is unnecessary.
Signed-off-by: Alberto Garcia
---
block/qcow2.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
diff --git a/block/qcow2.c b/block/qcow2.c
in
The current text corresponds to an earlier, simpler version of this
function and it does not explain how it works now.
Signed-off-by: Alberto Garcia
---
block/qcow2-cluster.c | 24 ++--
1 file changed, 14 insertions(+), 10 deletions(-)
diff --git a/block/qcow2-cluster.c b
].
Berto
Alberto Garcia (3):
qcow2: Fix removal of list members from BDRVQcow2State.cluster_allocs
qcow2: Don't check nb_clusters when removing l2meta from the list
qcow2: Rewrite the documentation of qcow2_alloc_cluster_offset()
block/qcow2-cluster.c | 27 +++---
block/qcow2.c
On Thu 03 Sep 2020 03:12:22 PM CEST, Max Reitz wrote:
> On my search for /(\.|->)nb_clusters/ to verify this, I noticed this
> comment for qcow2_alloc_cluster_offset():
>
> * If the cluster was already allocated, m->nb_clusters is set to 0 and
> * other fields in m are meaningless.
>
> Should
ged in commit
f50f88b9fe and nowadays nb_clusters is guaranteed to be > 0.
Signed-off-by: Alberto Garcia
---
block/qcow2-cluster.c | 3 --
block/qcow2.c | 4 +-
tests/qemu-iotests/305 | 75 ++
tests/qemu-iotests/305.out | 16
test
/* If fallocate() is not supported, fallback to full preallocation.
> */
With the missing braces in this if statement,
Reviewed-by: Alberto Garcia
Berto
On Thu 16 Jul 2020 01:33:59 PM CEST, Maxim Levitsky wrote:
> if (ret < 0) {
> +
> +Error *local_delete_err = NULL;
> +int r_del = bdrv_co_delete_file(bs, _delete_err);
> +/*
> + * ENOTSUP will happen if the block driver doesn't support
> + * the
On Mon 31 Aug 2020 04:01:26 PM CEST, Nir Soffer wrote:
> +static int preallocate_falloc(int fd, int64_t current_length, int64_t offset,
> + Error **errp)
> +{
> +#ifdef CONFIG_POSIX_FALLOCATE
> +int result;
> +
> +if (offset == current_length)
> +return
prone
> with the current code.
>
> Extract a helper for each of the preallocation modes (falloc, full, off)
> and leave only the common preparation and cleanup code in
> handle_aiocb_truncate().
>
> Signed-off-by: Nir Soffer
Reviewed-by: Alberto Garcia
Berto
This patch replaces instances of sizeof(uint64_t) in the qcow2 driver
with macros that indicate what those sizes are actually referring to.
Signed-off-by: Alberto Garcia
---
block/qcow2.h | 6 +++
block/qcow2-bitmap.c | 11 --
block/qcow2-cluster.c | 24 ++--
block
fine so there is no reason
why we cannot use that information.
After testing 4KB writes on an image that only contains zero clusters
this patch results in almost five times more IOPS.
Signed-off-by: Alberto Garcia
---
v2:
- Add new, simpler API: bdrv_is_unallocated_or_zero_above()
include/block
On Tue 25 Aug 2020 09:47:24 PM CEST, Brian Foster wrote:
> My fio fallocates the entire file by default with this command. Is that
> the intent of this particular test? I added --fallocate=none to my test
> runs to incorporate the allocation cost in the I/Os.
That wasn't intentional, you're
On Wed 26 Aug 2020 03:18:32 PM CEST, Kevin Wolf wrote:
>> My understanding is that writing 4K blocks requires a
>> read-modify-write because you must fetch a complete cluster from
>> deeper in the overlay chain before writing to the active
>> overlay. However, this does not explain the drop in
On Tue 25 Aug 2020 06:54:15 PM CEST, Brian Foster wrote:
> If I compare this 5m fio test between XFS and ext4 on a couple of my
> systems (with either no prealloc or full file prealloc), I end up seeing
> ext4 run slightly faster on my vm and XFS slightly faster on bare metal.
> Either way, I
On Tue 25 Aug 2020 04:01:14 PM CEST, Peter Maydell
wrote:
> On Tue, 25 Aug 2020 at 09:33, Max Reitz wrote:
>>
>> The following changes since commit 30aa19446d82358a30eac3b556b4d6641e00b7c1:
>>
>> Merge remote-tracking branch 'remotes/cschoenebeck/tags/pull-9p-20200812'
>> into staging
On Fri 21 Aug 2020 07:02:32 PM CEST, Brian Foster wrote:
>> I was running fio with --ramp_time=5 which ignores the first 5 seconds
>> of data in order to let performance settle, but if I remove that I can
>> see the effect more clearly. I can observe it with raw files (in 'off'
>> and 'prealloc'
On Sun 23 Aug 2020 11:59:07 PM CEST, Dave Chinner wrote:
>> >> Option 4 is described above as initial file preallocation whereas
>> >> option 1 is per 64k cluster prealloc. Prealloc mode mixup aside, Berto
>> >> is reporting that the initial file preallocation mode is slower than
>> >> the per
On Thu 20 Aug 2020 11:58:11 PM CEST, Dave Chinner wrote:
>> The virtual drive (/dev/vdb) is a freshly created qcow2 file stored on
>> the host (on an xfs or ext4 filesystem as the table above shows), and
>> it is attached to QEMU using a virtio-blk-pci device:
>>
>>-drive
On Fri 21 Aug 2020 02:59:44 PM CEST, Brian Foster wrote:
>> > Option 4 is described above as initial file preallocation whereas
>> > option 1 is per 64k cluster prealloc. Prealloc mode mixup aside, Berto
>> > is reporting that the initial file preallocation mode is slower than
>> > the per cluster
On Fri 21 Aug 2020 02:32:00 PM CEST, Vladimir Sementsov-Ogievskiy wrote:
> Hi!
>
> I'm sorry, I feel I already asked about it, but can't now find the answer.
>
> What are these ifs for?
>
>/* The data (middle) region must be immediately after the
> * start region */
>
On Fri 21 Aug 2020 01:42:52 PM CEST, Alberto Garcia wrote:
> On Fri 21 Aug 2020 01:05:06 PM CEST, Brian Foster wrote:
>>> > 1) off: for every write request QEMU initializes the cluster (64KB)
>>> > with fallocate(ZERO_RANGE) and then writes the 4KB of da
On Fri 21 Aug 2020 01:05:06 PM CEST, Brian Foster wrote:
>> > 1) off: for every write request QEMU initializes the cluster (64KB)
>> > with fallocate(ZERO_RANGE) and then writes the 4KB of data.
>> >
>> > 2) off w/o ZERO_RANGE: QEMU writes the 4KB of data and fills the rest
>> >
Cc: linux-xfs
On Wed 19 Aug 2020 07:53:00 PM CEST, Brian Foster wrote:
> In any event, if you're seeing unclear or unexpected performance
> deltas between certain XFS configurations or other fs', I think the
> best thing to do is post a more complete description of the workload,
>
On Wed 19 Aug 2020 05:37:12 PM CEST, Alberto Garcia wrote:
> I ran the test again on a newly created filesystem just to make sure,
> here are the full results (numbers are IOPS):
>
> |--+---+---|
> | preallocation
On Wed 19 Aug 2020 05:07:11 PM CEST, Kevin Wolf wrote:
>> I checked with xfs on my computer. I'm not very familiar with that
>> filesystem so I was using the default options and I didn't tune
>> anything.
>>
>> What I got with my tests (using fio):
>>
>> - Using extent_size_hint didn't make any
On Mon 17 Aug 2020 05:53:07 PM CEST, Kevin Wolf wrote:
>> > Or are you saying that ZERO_RANGE + pwrite on a sparse file (=
>> > cluster allocation) is faster for you than just the pwrite alone (=
>> > writing to already allocated cluster)?
>>
>> Yes, 20% faster in my tests (4KB random writes),
On Wed 19 Aug 2020 11:48:25 AM CEST, Vladimir Sementsov-Ogievskiy wrote:
>>> + * The top layer deferred to this layer, and because this
>>> layer is
>>> + * short, any zeroes that we synthesize beyond EOF behave as
>>> if they
>>> + * were allocated at this
On Wed 19 Aug 2020 03:36:07 AM CEST, Yi Li wrote:
> Signed-off-by: Yi Li
Reviewed-by: Alberto Garcia
Berto
On Wed 10 Jun 2020 02:04:26 PM CEST, Vladimir Sementsov-Ogievskiy wrote:
> These cases are fixed by previous patches around block_status and
> is_allocated.
Reviewed-by: Alberto Garcia
Berto
rlays has
> unallocated area at that place).
>
> Reusing bdrv_common_block_status_above fixes the issue and unifies code
> path.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy
> Reviewed-by: Eric Blake
Reviewed-by: Alberto Garcia
Berto
gt; So, support this corner case.
Reviewed-by: Alberto Garcia
Berto
On Wed 10 Jun 2020 02:04:23 PM CEST, Vladimir Sementsov-Ogievskiy wrote:
> In order to reuse bdrv_common_block_status_above in
> bdrv_is_allocated_above, let's support include_base parameter.
>
> Signed-off-by: Vladimir Sementsov-Ogievskiy
Reviewed-by: Alberto Garcia
Berto
On Wed 10 Jun 2020 02:04:22 PM CEST, Vladimir Sementsov-Ogievskiy wrote:
> + * The top layer deferred to this layer, and because this layer
> is
> + * short, any zeroes that we synthesize beyond EOF behave as if
> they
> + * were allocated at this layer
>
On Mon 17 Aug 2020 05:53:07 PM CEST, Kevin Wolf wrote:
> Maybe the difference is in allocating 64k at once instead of doing a
> separate allocation for every 4k block? But with the extent size hint
> patches to file-posix, we should allocate 1 MB at once by default now
> (if your test image was
On Mon 17 Aug 2020 12:10:19 PM CEST, Kevin Wolf wrote:
>> Since commit c8bb23cbdbe / QEMU 4.1.0 (and if the storage backend
>> allows it) writing to an image created with preallocation=metadata
>> can be slower (20% in my tests) than writing to an image with no
>> preallocation at all.
>
> A while
On Mon 17 Aug 2020 05:53:07 PM CEST, Kevin Wolf wrote:
>> > Or are you saying that ZERO_RANGE + pwrite on a sparse file (=
>> > cluster allocation) is faster for you than just the pwrite alone (=
>> > writing to already allocated cluster)?
>>
>> Yes, 20% faster in my tests (4KB random writes),
ed,
i.e. no backing file). This would make reading from them (and
writing to them, after this patch) faster.
Berto
Alberto Garcia (1):
qcow2: Skip copy-on-write when allocating a zero cluster
include/block/block.h | 2 +-
block/commit.c| 2 +-
block/io.c
fine so there is no reason
why we cannot use that information.
After testing 4KB writes on an image that only contains zero clusters
this patch results in almost five times more IOPS.
Signed-off-by: Alberto Garcia
---
include/block/block.h | 2 +-
block/commit.c| 2 +-
block/io.c
On Wed 05 Aug 2020 04:16:57 PM CEST, Kevin Wolf wrote:
>> nb_clusters is an int and there are more cases of
>>
>> nb_clusters << s->cluster_bits
>>
>> I can see at least these: handle_alloc(), qcow2_free_any_clusters(),
>> qcow2_alloc_cluster_abort().
>
> Actuallyx, handle_alloc() and
On Wed 05 Aug 2020 03:44:08 PM CEST, Alberto Garcia wrote:
> On Wed 05 Aug 2020 11:22:58 AM CEST, Tuguoyi wrote:
>> This patch fix it by casting @i to uint64_t before doing left shift
>> operation
>
> The patch seems fine and I also think that it's perhaps worth a test
>
On Wed 05 Aug 2020 11:22:58 AM CEST, Tuguoyi wrote:
> This patch fix it by casting @i to uint64_t before doing left shift
> operation
The patch seems fine and I also think that it's perhaps worth a test
case (although it only seems to happen with preallocation=falloc or full
so the test would
On Tue, Jul 14, 2020 at 02:56:57PM +0200, Max Reitz wrote:
> Thanks, fixed up patch 21 (by initializing expected_type to just
> anything, I chose QCOW2_SUBCLUSTER_NORMAL, which I preferred over
> just using 0), resolved some iotest conflicts (I’m sure, more are
> to come before the release, but
On Fri 10 Jul 2020 06:43:59 PM CEST, no-re...@patchew.org wrote:
> /tmp/qemu-test/src/block/qcow2-cluster.c:473:19: error: 'expected_type' may
> be used uninitialized in this function [-Werror=maybe-uninitialized]
> } else if (type != expected_type) {
>^
>
Now that the implementation of subclusters is complete we can finally
add the necessary options to create and read images with this feature,
which we call "extended L2 entries".
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
qapi/block
as a separate
function anymore so it's inlined into its caller.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
---
block/qcow2.h | 38 ---
block/qcow2-cluster.c | 150 ++
2 files changed, 92 insertions(+), 96 deletions(-)
diff --git
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
---
tests/qemu-iotests/271 | 901 +
tests/qemu-iotests/271.out | 726 ++
tests/qemu-iotests/group | 1 +
3 files changed, 1628 insertions(+)
create mode 100755 tests
.
2) if the tail area was compressed we are writing zeroes to the
head and the body areas, which are already zeroized.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
---
block/qcow2.h | 4 +--
block/qcow2-cluster.c | 81 +++
block
Compressed clusters always have the bitmap part of the extended L2
entry set to 0.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
---
block/qcow2-cluster.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index 5bdbb65e7b..6b5d0698d0
then we have to hide any possible stale
data and zero out the new clusters (see commit 955c7d6687 for more
details).
In this case the subclusters cannot be left as unallocated so the L2
bitmap must be updated.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block
This function is only used by qcow2_expand_zero_clusters() to
downgrade a qcow2 image to a previous version. This would require
transforming all extended L2 entries into normal L2 entries but this
is not a simple task and there are no plans to implement this at the
moment.
Signed-off-by: Alberto
and in order to detect errors more easily.
This patch makes qcow2_get_host_offset() return 0 on success and
puts the returned cluster type in a separate parameter. There are no
semantic changes.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
Reviewed-by: Vladimir Sementsov-Ogievskiy
---
block
This helper function tells us if a cluster is allocated (that is,
there is an associated host offset for it).
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2.h | 6 ++
1 file changed, 6 insertions(+)
diff --git a/block/qcow2.h b/block/qcow2.h
Extended L2 entries are bigger than normal L2 entries so this has an
impact on the amount of metadata needed for a qcow2 file.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
---
block/qcow2.c | 20 +---
1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/block
with zeroes the other
subclusters if we can guarantee that we are not overwriting existing
data. However this would waste more disk space, so we should first
evaluate if it's really worth doing.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
Reviewed-by: Vladimir Sementsov-Ogievskiy
---
block
that the image will read back as zeroes. If this is important for
the caller it should forbid it as qcow2_co_pdiscard() does (see
80f5c01183 for more details).
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2-cluster.c | 52
the get/set_l2_bitmap() functions that are
used to access the bitmaps. For convenience we allow calling
get_l2_bitmap() on images without subclusters. In this case the
returned value is always 0 and has no meaning.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
affected subclusters were already allocated). This
is detected in calculate_l2_meta(), and qcow2_alloc_cluster_link_l2()
is never called in those cases.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2-cluster.c | 18 ++
1 file changed, 18
When dealing with subcluster types there is a new value called
QCOW2_SUBCLUSTER_UNALLOCATED_ALLOC that has no equivalent in
QCow2ClusterType.
This patch handles that value in all places where subcluster types
are processed.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
Reviewed
We are going to need it in other places.
Signed-off-by: Alberto Garcia
Reviewed-by: Vladimir Sementsov-Ogievskiy
Reviewed-by: Max Reitz
---
block/qcow2-cluster.c | 34 +++---
1 file changed, 19 insertions(+), 15 deletions(-)
diff --git a/block/qcow2-cluster.c b
. This function returns the proper value for the image.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
---
block/qcow2.h | 9 +
block/qcow2-cluster.c | 12 ++--
block/qcow2-refcount.c | 14 --
block/qcow2.c | 8
4 files changed, 27 insertions
: if none of the subclusters are allocated
then we can clear the offset field and leave the bitmap untouched.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
---
block/qcow2-refcount.c | 16 +++-
tests/qemu-iotests/060.out | 2 +-
2 files changed, 12 insertions(+), 6 deletions
not need to be updated.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2-cluster.c | 36 +++-
1 file changed, 19 insertions(+), 17 deletions(-)
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index 492296a90f
it is perfectly possible to have an
allocated cluster with all its subclusters unallocated.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2.c | 7 ---
tests/qemu-iotests/206.out | 2 +-
2 files changed, 5 insertions(+), 4 deletions(-)
diff --git
reated as if they had exactly one
subcluster per cluster (i.e. subcluster_size = cluster_size).
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
Reviewed-by: Vladimir Sementsov-Ogievskiy
---
block/qcow2.h | 5 +
block/qcow2.c | 5 +
2 files changed, 10 insertions(+)
diff --git a/block/q
to
get_l2_entry() and set_l2_entry().
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
Reviewed-by: Vladimir Sementsov-Ogievskiy
---
block/qcow2.h | 12
block/qcow2-cluster.c | 63 ++
block/qcow2-refcount.c | 17
for subclusters.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2-cluster.c | 256 +++---
1 file changed, 141 insertions(+), 115 deletions(-)
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index 543f515c81
-off-by: Alberto Garcia
Reviewed-by: Max Reitz
Reviewed-by: Eric Blake
---
docs/interop/qcow2.txt | 68 --
docs/qcow2-cache.txt | 19 +++-
2 files changed, 83 insertions(+), 4 deletions(-)
diff --git a/docs/interop/qcow2.txt b/docs/interop/qcow2
of QCow2ClusterType with their QCow2SubclusterType
equivalents.
This patch only changes the data types, there are no semantic changes.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
Reviewed-by: Vladimir Sementsov-Ogievskiy
---
block/qcow2.h | 2 +-
block/qcow2-cluster.c | 10 +++
block
Like offset_into_cluster() and size_to_clusters(), but for
subclusters.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2.h | 10 ++
1 file changed, 10 insertions(+)
diff --git a/block/qcow2.h b/block/qcow2.h
index 2503374677..4fe31adfd3
and backing files if extended_l2
is set'
033/34:[] [--] 'qcow2: Assert that expand_zero_clusters_in_l1() does not
support subclusters'
034/34:[0006] [FC] 'iotests: Add tests for qcow2 images with extended L2
entries'
Alberto Garcia (34):
qcow2: Make Qcow2AioTask store the full host offset
qcow2
For a given offset, return the subcluster number within its cluster
(i.e. with 32 subclusters per cluster it returns a number between 0
and 31).
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
Reviewed-by: Vladimir Sementsov-Ogievskiy
---
block/qcow2.h | 5 +
1 file changed, 5
patch.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2.h | 126 +-
1 file changed, 125 insertions(+), 1 deletion(-)
diff --git a/block/qcow2.h b/block/qcow2.h
index 82b86f6cec..3aec6f452a 100644
() and l2meta_cow_end()
are not necessarily cluster-aligned anymore. We need to update the
calculation of old_start and old_end in handle_dependencies() to
guarantee that no two requests try to write on the same cluster.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
handle_alloc() creates a QCowL2Meta structure in order to update the
image metadata and perform the necessary copy-on-write operations.
This patch moves that code to a separate function so it can be used
from other places.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
---
block/qcow2
of a subcluster we can check the
rest efficiently by counting the number of adjacent ones (or zeroes)
in the bitmap. This is what this function does.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2-cluster.c | 51
with this patch
but it is documented now.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
Reviewed-by: Vladimir Sementsov-Ogievskiy
---
block/qcow2.c | 69 ++
block/trace-events | 2 +-
2 files changed, 34 insertions
value.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
Reviewed-by: Vladimir Sementsov-Ogievskiy
---
block/qcow2.h | 6 ++
1 file changed, 6 insertions(+)
diff --git a/block/qcow2.h b/block/qcow2.h
index eecbadc4cb..2064dd3d85 100644
--- a/block/qcow2.h
+++ b
-off-by: Alberto Garcia
Reviewed-by: Max Reitz
---
block/qcow2.h | 4 ++--
block/qcow2-cluster.c | 41 +++--
block/qcow2.c | 24 +++-
3 files changed, 32 insertions(+), 37 deletions(-)
diff --git a/block/qcow2.h b/block/qcow2
On Thu 09 Jul 2020 03:07:29 PM CEST, Max Reitz wrote:
> On 03.07.20 17:58, Alberto Garcia wrote:
>> Now that the implementation of subclusters is complete we can finally
>> add the necessary options to create and read images with this feature,
>> which we call "extended
Extended L2 entries are bigger than normal L2 entries so this has an
impact on the amount of metadata needed for a qcow2 file.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
---
block/qcow2.c | 20 +---
1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/block
it is perfectly possible to have an
allocated cluster with all its subclusters unallocated.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2.c | 7 ---
tests/qemu-iotests/206.out | 2 +-
2 files changed, 5 insertions(+), 4 deletions(-)
diff --git
that the image will read back as zeroes. If this is important for
the caller it should forbid it as qcow2_co_pdiscard() does (see
80f5c01183 for more details).
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2-cluster.c | 52
() and l2meta_cow_end()
are not necessarily cluster-aligned anymore. We need to update the
calculation of old_start and old_end in handle_dependencies() to
guarantee that no two requests try to write on the same cluster.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
This function is only used by qcow2_expand_zero_clusters() to
downgrade a qcow2 image to a previous version. This would require
transforming all extended L2 entries into normal L2 entries but this
is not a simple task and there are no plans to implement this at the
moment.
Signed-off-by: Alberto
and in order to detect errors more easily.
This patch makes qcow2_get_host_offset() return 0 on success and
puts the returned cluster type in a separate parameter. There are no
semantic changes.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
Reviewed-by: Vladimir Sementsov-Ogievskiy
---
block
the get/set_l2_bitmap() functions that are
used to access the bitmaps. For convenience we allow calling
get_l2_bitmap() on images without subclusters. In this case the
returned value is always 0 and has no meaning.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
Signed-off-by: Alberto Garcia
---
tests/qemu-iotests/271 | 901 +
tests/qemu-iotests/271.out | 724 +
tests/qemu-iotests/group | 1 +
3 files changed, 1626 insertions(+)
create mode 100755 tests/qemu-iotests/271
create
Now that the implementation of subclusters is complete we can finally
add the necessary options to create and read images with this feature,
which we call "extended L2 entries".
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
qapi/block
.
2) if the tail area was compressed we are writing zeroes to the
head and the body areas, which are already zeroized.
Signed-off-by: Alberto Garcia
---
block/qcow2.h | 4 +--
block/qcow2-cluster.c | 81 +++
block/qcow2.c | 33
as a separate
function anymore so it's inlined into its caller.
Signed-off-by: Alberto Garcia
---
block/qcow2.h | 38 ---
block/qcow2-cluster.c | 150 ++
2 files changed, 92 insertions(+), 96 deletions(-)
diff --git a/block/qcow2.h b/block
then we have to hide any possible stale
data and zero out the new clusters (see commit 955c7d6687 for more
details).
In this case the subclusters cannot be left as unallocated so the L2
bitmap must be updated.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block
When dealing with subcluster types there is a new value called
QCOW2_SUBCLUSTER_UNALLOCATED_ALLOC that has no equivalent in
QCow2ClusterType.
This patch handles that value in all places where subcluster types
are processed.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
Reviewed
This helper function tells us if a cluster is allocated (that is,
there is an associated host offset for it).
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2.h | 6 ++
1 file changed, 6 insertions(+)
diff --git a/block/qcow2.h b/block/qcow2.h
Like offset_into_cluster() and size_to_clusters(), but for
subclusters.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2.h | 10 ++
1 file changed, 10 insertions(+)
diff --git a/block/qcow2.h b/block/qcow2.h
index 2503374677..4fe31adfd3
of a subcluster we can check the
rest efficiently by counting the number of adjacent ones (or zeroes)
in the bitmap. This is what this function does.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2-cluster.c | 51
with zeroes the other
subclusters if we can guarantee that we are not overwriting existing
data. However this would waste more disk space, so we should first
evaluate if it's really worth doing.
Signed-off-by: Alberto Garcia
Reviewed-by: Max Reitz
Reviewed-by: Vladimir Sementsov-Ogievskiy
---
block
not need to be updated.
Signed-off-by: Alberto Garcia
Reviewed-by: Eric Blake
Reviewed-by: Max Reitz
---
block/qcow2-cluster.c | 36 +++-
1 file changed, 19 insertions(+), 17 deletions(-)
diff --git a/block/qcow2-cluster.c b/block/qcow2-cluster.c
index 492296a90f
201 - 300 of 2996 matches
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