Now dirty bitmaps can be loaded but there is no their saving. Add code for
dirty bitmap storage.
Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
---
block/parallels-ext.c | 168 ++++++++++++++++++++++++++++++++++++++++++
block/parallels.c | 16 +++-
block/parallels.h | 5 ++
3 files changed, 187 insertions(+), 2 deletions(-)
diff --git a/block/parallels-ext.c b/block/parallels-ext.c
index b4e14c88f2..c83d1ea393 100644
--- a/block/parallels-ext.c
+++ b/block/parallels-ext.c
@@ -24,6 +24,7 @@
*/
#include "qemu/osdep.h"
+#include "qemu/error-report.h"
#include "qapi/error.h"
#include "block/block-io.h"
#include "block/block_int.h"
@@ -300,3 +301,170 @@ out:
return ret;
}
+
+static void GRAPH_RDLOCK parallels_save_bitmap(BlockDriverState *bs,
+ BdrvDirtyBitmap *bitmap,
+ uint8_t **buf, int *buf_size)
+{
+ BDRVParallelsState *s = bs->opaque;
+ ParallelsFeatureHeader *fh;
+ ParallelsDirtyBitmapFeature *bh;
+ uint64_t *l1_table, l1_size, granularity, limit;
+ int64_t bm_size, ser_size, offset, buf_used;
+ int64_t alloc_size = 1;
+ const char *name;
+ uint8_t *bm_buf;
+ QemuUUID uuid;
+ int ret = 0;
+
+ if (!bdrv_dirty_bitmap_get_persistence(bitmap) ||
+ bdrv_dirty_bitmap_inconsistent(bitmap)) {
+ return;
+ }
+
+ bm_size = bdrv_dirty_bitmap_size(bitmap);
+ granularity = bdrv_dirty_bitmap_granularity(bitmap);
+ limit = bdrv_dirty_bitmap_serialization_coverage(s->cluster_size, bitmap);
+ ser_size = bdrv_dirty_bitmap_serialization_size(bitmap, 0, bm_size);
+ l1_size = DIV_ROUND_UP(ser_size, s->cluster_size);
+
+ buf_used = l1_size * 8 + sizeof(*fh) + sizeof(*bh);
+ /* Check if there is enough space for the final section */
+ if (*buf_size - buf_used < sizeof(*fh)) {
+ return;
+ }
+
+ name = bdrv_dirty_bitmap_name(bitmap);
+ ret = qemu_uuid_parse(name, &uuid);
+ if (ret < 0) {
+ error_report("Can't save dirty bitmap: ID parsing error: '%s'", name);
+ return;
+ }
+
+ fh = (ParallelsFeatureHeader *)*buf;
+ bh = (ParallelsDirtyBitmapFeature *)(*buf + sizeof(*fh));
+ l1_table = (uint64_t *)((uint8_t *)bh + sizeof(*bh));
+
+ fh->magic = cpu_to_le64(PARALLELS_DIRTY_BITMAP_FEATURE_MAGIC);
+ fh->data_size = cpu_to_le32(l1_size * 8 + sizeof(*bh));
+
+ bh->l1_size = cpu_to_le32(l1_size);
+ bh->size = cpu_to_le64(bm_size >> BDRV_SECTOR_BITS);
+ bh->granularity = cpu_to_le32(granularity >> BDRV_SECTOR_BITS);
+ memcpy(bh->id, &uuid, sizeof(uuid));
+
+ bm_buf = qemu_blockalign(bs, s->cluster_size);
+
+ offset = 0;
+ while ((offset = bdrv_dirty_bitmap_next_dirty(bitmap, offset, bm_size)) >= 0) {
+ uint64_t idx = offset / limit;
+ int64_t cluster_off, end, write_size;
+
+ offset = QEMU_ALIGN_DOWN(offset, limit);
+ end = MIN(bm_size, offset + limit);
+ write_size = bdrv_dirty_bitmap_serialization_size(bitmap, offset,
+ end - offset);
+ assert(write_size <= s->cluster_size);
+
+ bdrv_dirty_bitmap_serialize_part(bitmap, bm_buf, offset, end - offset);
+ if (write_size < s->cluster_size) {
+ memset(bm_buf + write_size, 0, s->cluster_size - write_size);
+ }
+
+ cluster_off = parallels_allocate_host_clusters(bs, &alloc_size);
+ if (cluster_off <= 0) {
+ goto end;
+ }
+
+ ret = bdrv_pwrite(bs->file, cluster_off, s->cluster_size, bm_buf, 0);
+ if (ret < 0) {
+ memset(&fh->magic, 0, sizeof(fh->magic));
+ parallels_mark_unused(bs, s->used_bmap, s->used_bmap_size,
+ cluster_off, 1);
+ goto end;
+ }
+
+ l1_table[idx] = cpu_to_le64(cluster_off >> BDRV_SECTOR_BITS);
+ offset = end;
+ }
+
+ *buf_size -= buf_used;
+ *buf += buf_used;
+
+end:
+ qemu_vfree(bm_buf);
+}
+
+void GRAPH_RDLOCK
+parallels_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error **errp)
+{
+ BDRVParallelsState *s = bs->opaque;
+ BdrvDirtyBitmap *bitmap;
+ ParallelsFormatExtensionHeader *eh;
+ int remaining = s->cluster_size;
+ uint8_t *buf, *pos;
+ int64_t header_off, alloc_size = 1;
+ g_autofree uint8_t *hash = NULL;
+ size_t hash_len = 0;
+ int ret;
+
+ s->header->ext_off = 0;
+
+ if (!bdrv_has_named_bitmaps(bs)) {
+ return;
+ }
+
+ buf = qemu_blockalign0(bs, s->cluster_size);
+
+ eh = (ParallelsFormatExtensionHeader *)buf;
+ pos = buf + sizeof(*eh);
+
+ eh->magic = cpu_to_le64(PARALLELS_FORMAT_EXTENSION_MAGIC);
+
+ FOR_EACH_DIRTY_BITMAP(bs, bitmap) {
+ parallels_save_bitmap(bs, bitmap, &pos, &remaining);
+ }
+
+ header_off = parallels_allocate_host_clusters(bs, &alloc_size);
+ if (header_off < 0) {
+ error_report("Can't save dirty bitmap: cluster allocation error");
+ ret = header_off;
+ goto end;
+ }
+
+ ret = qcrypto_hash_bytes(QCRYPTO_HASH_ALG_MD5,
+ (const char *)(buf + sizeof(*eh)),
+ s->cluster_size - sizeof(*eh),
+ &hash, &hash_len, errp);
+ if (ret < 0 || hash_len != sizeof(eh->check_sum)) {
+ error_report("Can't save dirty bitmap: hash error");
+ ret = -EINVAL;
+ goto end;
+ }
+ memcpy(eh->check_sum, hash, hash_len);
+
+ ret = bdrv_pwrite(bs->file, header_off, s->cluster_size, buf, 0);
+ if (ret < 0) {
+ error_report("Can't save dirty bitmap: IO error");
+ parallels_mark_unused(bs, s->used_bmap, s->used_bmap_size,
+ header_off, 1);
+ goto end;
+ }
+
+ s->header->ext_off = cpu_to_le64(header_off / BDRV_SECTOR_SIZE);
+end:
+ qemu_vfree(buf);
+}
+
+bool coroutine_fn parallels_co_can_store_new_dirty_bitmap(BlockDriverState *bs,
+ const char *name,
+ uint32_t granularity,
+ Error **errp)
+{
+ if (bdrv_find_dirty_bitmap(bs, name)) {
+ error_setg(errp, "Bitmap already exists: %s", name);
+ return false;
+ }
+
+ return true;
+}
diff --git a/block/parallels.c b/block/parallels.c
index f38dd2309c..a49922c6a7 100644
--- a/block/parallels.c
+++ b/block/parallels.c
@@ -1466,14 +1466,25 @@ fail:
static int GRAPH_RDLOCK parallels_inactivate(BlockDriverState *bs)
{
BDRVParallelsState *s = bs->opaque;
+ Error *err = NULL;
int ret;
+ parallels_store_persistent_dirty_bitmaps(bs, &err);
+ if (err != NULL) {
+ error_reportf_err(err, "Lost persistent bitmaps during "
+ "inactivation of node '%s': ",
+ bdrv_get_device_or_node_name(bs));
+ }
+
s->header->inuse = 0;
parallels_update_header(bs);
/* errors are ignored, so we might as well pass exact=true */
- ret = bdrv_truncate(bs->file, s->data_end << BDRV_SECTOR_BITS, true,
- PREALLOC_MODE_OFF, 0, NULL);
+ ret = bdrv_truncate(bs->file, s->data_end << BDRV_SECTOR_BITS,
+ true, PREALLOC_MODE_OFF, 0, NULL);
+ if (ret < 0) {
+ error_report("Failed to truncate image: %s", strerror(-ret));
+ }
return ret;
}
@@ -1525,6 +1536,7 @@ static BlockDriver bdrv_parallels = {
.bdrv_co_pdiscard = parallels_co_pdiscard,
.bdrv_co_pwrite_zeroes = parallels_co_pwrite_zeroes,
.bdrv_inactivate = parallels_inactivate,
+ .bdrv_co_can_store_new_dirty_bitmap = parallels_co_can_store_new_dirty_bitmap,
};
static void bdrv_parallels_init(void)
diff --git a/block/parallels.h b/block/parallels.h
index 493c89e976..9db4f5c908 100644
--- a/block/parallels.h
+++ b/block/parallels.h
@@ -101,5 +101,10 @@ int64_t GRAPH_RDLOCK parallels_allocate_host_clusters(BlockDriverState *bs,
int GRAPH_RDLOCK
parallels_read_format_extension(BlockDriverState *bs, int64_t ext_off,
Error **errp);
+void GRAPH_RDLOCK
+parallels_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error **errp);
+bool coroutine_fn
+parallels_co_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name,
+ uint32_t granularity, Error **errp);
#endif
--
2.40.1On 12/28/23 11:12, Alexander Ivanov wrote:
> Now dirty bitmaps can be loaded but there is no their saving. Add code for
> dirty bitmap storage.
>
> Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
> ---
> block/parallels-ext.c | 168 ++++++++++++++++++++++++++++++++++++++++++
> block/parallels.c | 16 +++-
> block/parallels.h | 5 ++
> 3 files changed, 187 insertions(+), 2 deletions(-)
>
> diff --git a/block/parallels-ext.c b/block/parallels-ext.c
> index b4e14c88f2..c83d1ea393 100644
> --- a/block/parallels-ext.c
> +++ b/block/parallels-ext.c
> @@ -24,6 +24,7 @@
> */
>
> #include "qemu/osdep.h"
> +#include "qemu/error-report.h"
> #include "qapi/error.h"
> #include "block/block-io.h"
> #include "block/block_int.h"
> @@ -300,3 +301,170 @@ out:
>
> return ret;
> }
> +
> +static void GRAPH_RDLOCK parallels_save_bitmap(BlockDriverState *bs,
> + BdrvDirtyBitmap *bitmap,
> + uint8_t **buf, int *buf_size)
Do we need a error?
> +{
> + BDRVParallelsState *s = bs->opaque;
> + ParallelsFeatureHeader *fh;
> + ParallelsDirtyBitmapFeature *bh;
> + uint64_t *l1_table, l1_size, granularity, limit;
I would say that 'limit' here means 'bits_in_cluster'
We are writing the new code and I would prefer if we
would have bits, bytes, clusters, sectors etc are
clearly seen in variable names. It is quite complex
to track various measurables.
> + int64_t bm_size, ser_size, offset, buf_used;
> + int64_t alloc_size = 1;
> + const char *name;
> + uint8_t *bm_buf;
> + QemuUUID uuid;
> + int ret = 0;
> +
> + if (!bdrv_dirty_bitmap_get_persistence(bitmap) ||
> + bdrv_dirty_bitmap_inconsistent(bitmap)) {
> + return;
> + }
> +
> + bm_size = bdrv_dirty_bitmap_size(bitmap);
> + granularity = bdrv_dirty_bitmap_granularity(bitmap);
> + limit = bdrv_dirty_bitmap_serialization_coverage(s->cluster_size, bitmap);
> + ser_size = bdrv_dirty_bitmap_serialization_size(bitmap, 0, bm_size);
> + l1_size = DIV_ROUND_UP(ser_size, s->cluster_size);
> +
> + buf_used = l1_size * 8 + sizeof(*fh) + sizeof(*bh);
As far as I can see, bdrv_dirty_bitmap_serialization_size() returns bytes.
That is correct. Thus multiplying it by 8 seems fatal mistake.
I am also quite unsure that we should roundup to the cluster, that
will occupy more clusters than needed. Can you please take a look
here
https://src.openvz.org/users/ibazhitov/repos/ploop/browse/tools/ploop-cbt.c
> + /* Check if there is enough space for the final section */
> + if (*buf_size - buf_used < sizeof(*fh)) {
> + return;
> + }
> +
> + name = bdrv_dirty_bitmap_name(bitmap);
> + ret = qemu_uuid_parse(name, &uuid);
> + if (ret < 0) {
> + error_report("Can't save dirty bitmap: ID parsing error: '%s'", name);
> + return;
> + }
> +
> + fh = (ParallelsFeatureHeader *)*buf;
> + bh = (ParallelsDirtyBitmapFeature *)(*buf + sizeof(*fh));
bh = fh + 1 ?
> + l1_table = (uint64_t *)((uint8_t *)bh + sizeof(*bh));
l1_table = bh + 1 ?
> +
> + fh->magic = cpu_to_le64(PARALLELS_DIRTY_BITMAP_FEATURE_MAGIC);
> + fh->data_size = cpu_to_le32(l1_size * 8 + sizeof(*bh));
I am quite concerned here. Please compare with
int save_dirty_bitmap(int devfd, struct delta *delta, off_t offset,
void *buf, __u32 *size, void *or_data, writer_fn wr,
void *data)
{
int ret = 0;
struct ploop_pvd_header *vh;
size_t block_size;
__u64 bits, bytes, *p;
__u32 byte_granularity;
void *block;
struct ploop_pvd_dirty_bitmap_raw *raw = (struct
ploop_pvd_dirty_bitmap_raw *)buf;
char x[50];
vh = (struct ploop_pvd_header *)delta->hdr0;
/* granularity and uuid */
if ((ret = cbt_get_dirty_bitmap_metadata(devfd, raw->m_Id,
&raw->m_Granularity)))
return ret;
raw->m_Granularity /= SECTOR_SIZE;
block_size = vh->m_Sectors * SECTOR_SIZE;
if (p_memalign((void **)&block, 4096, block_size))
return SYSEXIT_MALLOC;
raw->m_Size = vh->m_SizeInSectors_v2;
byte_granularity = raw->m_Granularity * SECTOR_SIZE;
bits = ((raw->m_Size + raw->m_Granularity - 1) / raw->m_Granularity);
bytes = (bits + 7) >> 3;
raw->m_L1Size = (bytes + block_size - 1) / block_size;
which means that the header is rotten. In that case can you pls
take a look why this has not been caught by tests?
> +
> + bh->l1_size = cpu_to_le32(l1_size);
> + bh->size = cpu_to_le64(bm_size >> BDRV_SECTOR_BITS);
> + bh->granularity = cpu_to_le32(granularity >> BDRV_SECTOR_BITS);
> + memcpy(bh->id, &uuid, sizeof(uuid));
> +
> + bm_buf = qemu_blockalign(bs, s->cluster_size);
> +
> + offset = 0;
> + while ((offset = bdrv_dirty_bitmap_next_dirty(bitmap, offset, bm_size)) >= 0) {
> + uint64_t idx = offset / limit;
> + int64_t cluster_off, end, write_size;
> +
> + offset = QEMU_ALIGN_DOWN(offset, limit);
> + end = MIN(bm_size, offset + limit);
> + write_size = bdrv_dirty_bitmap_serialization_size(bitmap, offset,
> + end - offset);
> + assert(write_size <= s->cluster_size);
> +
> + bdrv_dirty_bitmap_serialize_part(bitmap, bm_buf, offset, end - offset);
> + if (write_size < s->cluster_size) {
> + memset(bm_buf + write_size, 0, s->cluster_size - write_size);
> + }
> +
> + cluster_off = parallels_allocate_host_clusters(bs, &alloc_size);
> + if (cluster_off <= 0) {
> + goto end;
> + }
> +
> + ret = bdrv_pwrite(bs->file, cluster_off, s->cluster_size, bm_buf, 0);
> + if (ret < 0) {
> + memset(&fh->magic, 0, sizeof(fh->magic));
> + parallels_mark_unused(bs, s->used_bmap, s->used_bmap_size,
> + cluster_off, 1);
That is incomplete. You have to clean all clusters inside of the
extension.
> + goto end;
> + }
> +
> + l1_table[idx] = cpu_to_le64(cluster_off >> BDRV_SECTOR_BITS);
> + offset = end;
> + }
> +
> + *buf_size -= buf_used;
> + *buf += buf_used;
> +
> +end:
> + qemu_vfree(bm_buf);
> +}
> +
> +void GRAPH_RDLOCK
> +parallels_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error **errp)
> +{
> + BDRVParallelsState *s = bs->opaque;
> + BdrvDirtyBitmap *bitmap;
> + ParallelsFormatExtensionHeader *eh;
> + int remaining = s->cluster_size;
> + uint8_t *buf, *pos;
> + int64_t header_off, alloc_size = 1;
> + g_autofree uint8_t *hash = NULL;
> + size_t hash_len = 0;
> + int ret;
> +
> + s->header->ext_off = 0;
> +
> + if (!bdrv_has_named_bitmaps(bs)) {
> + return;
> + }
> +
> + buf = qemu_blockalign0(bs, s->cluster_size);
> +
> + eh = (ParallelsFormatExtensionHeader *)buf;
> + pos = buf + sizeof(*eh);
> +
> + eh->magic = cpu_to_le64(PARALLELS_FORMAT_EXTENSION_MAGIC);
> +
> + FOR_EACH_DIRTY_BITMAP(bs, bitmap) {
> + parallels_save_bitmap(bs, bitmap, &pos, &remaining);
> + }
> +
> + header_off = parallels_allocate_host_clusters(bs, &alloc_size);
> + if (header_off < 0) {
> + error_report("Can't save dirty bitmap: cluster allocation error");
> + ret = header_off;
> + goto end;
> + }
> +
> + ret = qcrypto_hash_bytes(QCRYPTO_HASH_ALG_MD5,
> + (const char *)(buf + sizeof(*eh)),
> + s->cluster_size - sizeof(*eh),
> + &hash, &hash_len, errp);
> + if (ret < 0 || hash_len != sizeof(eh->check_sum)) {
> + error_report("Can't save dirty bitmap: hash error");
> + ret = -EINVAL;
> + goto end;
> + }
> + memcpy(eh->check_sum, hash, hash_len);
> +
> + ret = bdrv_pwrite(bs->file, header_off, s->cluster_size, buf, 0);
> + if (ret < 0) {
> + error_report("Can't save dirty bitmap: IO error");
> + parallels_mark_unused(bs, s->used_bmap, s->used_bmap_size,
> + header_off, 1);
> + goto end;
> + }
> +
> + s->header->ext_off = cpu_to_le64(header_off / BDRV_SECTOR_SIZE);
> +end:
> + qemu_vfree(buf);
> +}
> +
> +bool coroutine_fn parallels_co_can_store_new_dirty_bitmap(BlockDriverState *bs,
> + const char *name,
> + uint32_t granularity,
> + Error **errp)
> +{
> + if (bdrv_find_dirty_bitmap(bs, name)) {
> + error_setg(errp, "Bitmap already exists: %s", name);
> + return false;
> + }
> +
> + return true;
> +}
> diff --git a/block/parallels.c b/block/parallels.c
> index f38dd2309c..a49922c6a7 100644
> --- a/block/parallels.c
> +++ b/block/parallels.c
> @@ -1466,14 +1466,25 @@ fail:
> static int GRAPH_RDLOCK parallels_inactivate(BlockDriverState *bs)
> {
> BDRVParallelsState *s = bs->opaque;
> + Error *err = NULL;
> int ret;
>
> + parallels_store_persistent_dirty_bitmaps(bs, &err);
> + if (err != NULL) {
For me this looks quite odd, indirect check for error. Not good
> + error_reportf_err(err, "Lost persistent bitmaps during "
> + "inactivation of node '%s': ",
> + bdrv_get_device_or_node_name(bs));
> + }
> +
> s->header->inuse = 0;
> parallels_update_header(bs);
>
> /* errors are ignored, so we might as well pass exact=true */
> - ret = bdrv_truncate(bs->file, s->data_end << BDRV_SECTOR_BITS, true,
> - PREALLOC_MODE_OFF, 0, NULL);
> + ret = bdrv_truncate(bs->file, s->data_end << BDRV_SECTOR_BITS,
> + true, PREALLOC_MODE_OFF, 0, NULL);
> + if (ret < 0) {
> + error_report("Failed to truncate image: %s", strerror(-ret));
> + }
>
> return ret;
> }
> @@ -1525,6 +1536,7 @@ static BlockDriver bdrv_parallels = {
> .bdrv_co_pdiscard = parallels_co_pdiscard,
> .bdrv_co_pwrite_zeroes = parallels_co_pwrite_zeroes,
> .bdrv_inactivate = parallels_inactivate,
> + .bdrv_co_can_store_new_dirty_bitmap = parallels_co_can_store_new_dirty_bitmap,
> };
>
> static void bdrv_parallels_init(void)
> diff --git a/block/parallels.h b/block/parallels.h
> index 493c89e976..9db4f5c908 100644
> --- a/block/parallels.h
> +++ b/block/parallels.h
> @@ -101,5 +101,10 @@ int64_t GRAPH_RDLOCK parallels_allocate_host_clusters(BlockDriverState *bs,
> int GRAPH_RDLOCK
> parallels_read_format_extension(BlockDriverState *bs, int64_t ext_off,
> Error **errp);
> +void GRAPH_RDLOCK
> +parallels_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error **errp);
> +bool coroutine_fn
> +parallels_co_can_store_new_dirty_bitmap(BlockDriverState *bs, const char *name,
> + uint32_t granularity, Error **errp);
>
> #endif
On 1/18/24 14:27, Denis V. Lunev wrote:
> On 12/28/23 11:12, Alexander Ivanov wrote:
>> Now dirty bitmaps can be loaded but there is no their saving. Add
>> code for
>> dirty bitmap storage.
>>
>> Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com>
>> ---
>> block/parallels-ext.c | 168 ++++++++++++++++++++++++++++++++++++++++++
>> block/parallels.c | 16 +++-
>> block/parallels.h | 5 ++
>> 3 files changed, 187 insertions(+), 2 deletions(-)
>>
>> diff --git a/block/parallels-ext.c b/block/parallels-ext.c
>> index b4e14c88f2..c83d1ea393 100644
>> --- a/block/parallels-ext.c
>> +++ b/block/parallels-ext.c
>> @@ -24,6 +24,7 @@
>> */
>> #include "qemu/osdep.h"
>> +#include "qemu/error-report.h"
>> #include "qapi/error.h"
>> #include "block/block-io.h"
>> #include "block/block_int.h"
>> @@ -300,3 +301,170 @@ out:
>> return ret;
>> }
>> +
>> +static void GRAPH_RDLOCK parallels_save_bitmap(BlockDriverState *bs,
>> + BdrvDirtyBitmap *bitmap,
>> + uint8_t **buf, int
>> *buf_size)
> Do we need a error?
I think no. We save bitmaps in a loop. If some bitmap has a problem it
would be better
just to print an error message and try to save other bitmaps.
>
>> +{
>> + BDRVParallelsState *s = bs->opaque;
>> + ParallelsFeatureHeader *fh;
>> + ParallelsDirtyBitmapFeature *bh;
>> + uint64_t *l1_table, l1_size, granularity, limit;
> I would say that 'limit' here means 'bits_in_cluster'
>
> We are writing the new code and I would prefer if we
> would have bits, bytes, clusters, sectors etc are
> clearly seen in variable names. It is quite complex
> to track various measurables.
OK
>> + int64_t bm_size, ser_size, offset, buf_used;
>> + int64_t alloc_size = 1;
>> + const char *name;
>> + uint8_t *bm_buf;
>> + QemuUUID uuid;
>> + int ret = 0;
>> +
>> + if (!bdrv_dirty_bitmap_get_persistence(bitmap) ||
>> + bdrv_dirty_bitmap_inconsistent(bitmap)) {
>> + return;
>> + }
>> +
>> + bm_size = bdrv_dirty_bitmap_size(bitmap);
>> + granularity = bdrv_dirty_bitmap_granularity(bitmap);
>> + limit =
>> bdrv_dirty_bitmap_serialization_coverage(s->cluster_size, bitmap);
>> + ser_size = bdrv_dirty_bitmap_serialization_size(bitmap, 0,
>> bm_size);
>> + l1_size = DIV_ROUND_UP(ser_size, s->cluster_size);
>> +
>> + buf_used = l1_size * 8 + sizeof(*fh) + sizeof(*bh);
> As far as I can see, bdrv_dirty_bitmap_serialization_size() returns
> bytes.
> That is correct. Thus multiplying it by 8 seems fatal mistake.
l1_size is amount of entries in l1_table. Every entry has 8 bytes size
and corresponds
to one cluster containing a part of a bitmap.
> I am also quite unsure that we should roundup to the cluster, that
> will occupy more clusters than needed. Can you please take a look
> here
> https://src.openvz.org/users/ibazhitov/repos/ploop/browse/tools/ploop-cbt.c
>
Why shouldn't we? We need to have l1_table which should be able to contain
all the bitmap data. Note: there is not a ROUND_UP(), but DIV_ROUND_UP().
>> + /* Check if there is enough space for the final section */
>> + if (*buf_size - buf_used < sizeof(*fh)) {
>> + return;
>> + }
>> +
>> + name = bdrv_dirty_bitmap_name(bitmap);
>> + ret = qemu_uuid_parse(name, &uuid);
>> + if (ret < 0) {
>> + error_report("Can't save dirty bitmap: ID parsing error:
>> '%s'", name);
>> + return;
>> + }
>> +
>> + fh = (ParallelsFeatureHeader *)*buf;
>> + bh = (ParallelsDirtyBitmapFeature *)(*buf + sizeof(*fh));
> bh = fh + 1 ?
>> + l1_table = (uint64_t *)((uint8_t *)bh + sizeof(*bh));
> l1_table = bh + 1 ?
Yes, it's better.
>> +
>> + fh->magic = cpu_to_le64(PARALLELS_DIRTY_BITMAP_FEATURE_MAGIC);
>> + fh->data_size = cpu_to_le32(l1_size * 8 + sizeof(*bh));
> I am quite concerned here. Please compare with
>
> int save_dirty_bitmap(int devfd, struct delta *delta, off_t offset,
> void *buf, __u32 *size, void *or_data, writer_fn wr,
> void *data)
> {
> int ret = 0;
> struct ploop_pvd_header *vh;
> size_t block_size;
> __u64 bits, bytes, *p;
> __u32 byte_granularity;
> void *block;
> struct ploop_pvd_dirty_bitmap_raw *raw = (struct
> ploop_pvd_dirty_bitmap_raw *)buf;
> char x[50];
>
> vh = (struct ploop_pvd_header *)delta->hdr0;
>
> /* granularity and uuid */
> if ((ret = cbt_get_dirty_bitmap_metadata(devfd, raw->m_Id,
> &raw->m_Granularity)))
> return ret;
> raw->m_Granularity /= SECTOR_SIZE;
>
> block_size = vh->m_Sectors * SECTOR_SIZE;
> if (p_memalign((void **)&block, 4096, block_size))
> return SYSEXIT_MALLOC;
>
> raw->m_Size = vh->m_SizeInSectors_v2;
>
> byte_granularity = raw->m_Granularity * SECTOR_SIZE;
> bits = ((raw->m_Size + raw->m_Granularity - 1) / raw->m_Granularity);
> bytes = (bits + 7) >> 3;
> raw->m_L1Size = (bytes + block_size - 1) / block_size;
>
> which means that the header is rotten. In that case can you pls
> take a look why this has not been caught by tests?
It looks the same if block_size is cluster size in bytes.
bytes - bitmap size in bytes
raw->m_L1Size - bitmap size in clusters
In my code fh->data_size is l1_table size (8 bytes entry for each bitmap
cluster) plus
dirty bitmap feature header.
>
>> +
>> + bh->l1_size = cpu_to_le32(l1_size);
>> + bh->size = cpu_to_le64(bm_size >> BDRV_SECTOR_BITS);
>> + bh->granularity = cpu_to_le32(granularity >> BDRV_SECTOR_BITS);
>> + memcpy(bh->id, &uuid, sizeof(uuid));
>> +
>> + bm_buf = qemu_blockalign(bs, s->cluster_size);
>> +
>> + offset = 0;
>> + while ((offset = bdrv_dirty_bitmap_next_dirty(bitmap, offset,
>> bm_size)) >= 0) {
>> + uint64_t idx = offset / limit;
>> + int64_t cluster_off, end, write_size;
>> +
>> + offset = QEMU_ALIGN_DOWN(offset, limit);
>> + end = MIN(bm_size, offset + limit);
>> + write_size = bdrv_dirty_bitmap_serialization_size(bitmap,
>> offset,
>> + end -
>> offset);
>> + assert(write_size <= s->cluster_size);
>> +
>> + bdrv_dirty_bitmap_serialize_part(bitmap, bm_buf, offset, end
>> - offset);
>> + if (write_size < s->cluster_size) {
>> + memset(bm_buf + write_size, 0, s->cluster_size -
>> write_size);
>> + }
>> +
>> + cluster_off = parallels_allocate_host_clusters(bs,
>> &alloc_size);
>> + if (cluster_off <= 0) {
>> + goto end;
>> + }
>
>
>
>> +
>> + ret = bdrv_pwrite(bs->file, cluster_off, s->cluster_size,
>> bm_buf, 0);
>> + if (ret < 0) {
>> + memset(&fh->magic, 0, sizeof(fh->magic));
>> + parallels_mark_unused(bs, s->used_bmap, s->used_bmap_size,
>> + cluster_off, 1);
> That is incomplete. You have to clean all clusters inside of the
> extension.
OK
>
>> + goto end;
>> + }
>> +
>> + l1_table[idx] = cpu_to_le64(cluster_off >> BDRV_SECTOR_BITS);
>> + offset = end;
>> + }
>> +
>> + *buf_size -= buf_used;
>> + *buf += buf_used;
>> +
>> +end:
>> + qemu_vfree(bm_buf);
>> +}
>> +
>> +void GRAPH_RDLOCK
>> +parallels_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error
>> **errp)
>> +{
>> + BDRVParallelsState *s = bs->opaque;
>> + BdrvDirtyBitmap *bitmap;
>> + ParallelsFormatExtensionHeader *eh;
>> + int remaining = s->cluster_size;
>> + uint8_t *buf, *pos;
>> + int64_t header_off, alloc_size = 1;
>> + g_autofree uint8_t *hash = NULL;
>> + size_t hash_len = 0;
>> + int ret;
>> +
>> + s->header->ext_off = 0;
>> +
>> + if (!bdrv_has_named_bitmaps(bs)) {
>> + return;
>> + }
>> +
>> + buf = qemu_blockalign0(bs, s->cluster_size);
>> +
>> + eh = (ParallelsFormatExtensionHeader *)buf;
>> + pos = buf + sizeof(*eh);
>> +
>> + eh->magic = cpu_to_le64(PARALLELS_FORMAT_EXTENSION_MAGIC);
>> +
>> + FOR_EACH_DIRTY_BITMAP(bs, bitmap) {
>> + parallels_save_bitmap(bs, bitmap, &pos, &remaining);
>> + }
>> +
>> + header_off = parallels_allocate_host_clusters(bs, &alloc_size);
>> + if (header_off < 0) {
>> + error_report("Can't save dirty bitmap: cluster allocation
>> error");
>> + ret = header_off;
>> + goto end;
>> + }
>> +
>> + ret = qcrypto_hash_bytes(QCRYPTO_HASH_ALG_MD5,
>> + (const char *)(buf + sizeof(*eh)),
>> + s->cluster_size - sizeof(*eh),
>> + &hash, &hash_len, errp);
>> + if (ret < 0 || hash_len != sizeof(eh->check_sum)) {
>> + error_report("Can't save dirty bitmap: hash error");
>> + ret = -EINVAL;
>> + goto end;
>> + }
>> + memcpy(eh->check_sum, hash, hash_len);
>> +
>> + ret = bdrv_pwrite(bs->file, header_off, s->cluster_size, buf, 0);
>> + if (ret < 0) {
>> + error_report("Can't save dirty bitmap: IO error");
>> + parallels_mark_unused(bs, s->used_bmap, s->used_bmap_size,
>> + header_off, 1);
>> + goto end;
>> + }
>> +
>> + s->header->ext_off = cpu_to_le64(header_off / BDRV_SECTOR_SIZE);
>> +end:
>> + qemu_vfree(buf);
>> +}
>> +
>> +bool coroutine_fn
>> parallels_co_can_store_new_dirty_bitmap(BlockDriverState *bs,
>> + const char
>> *name,
>> + uint32_t granularity,
>> + Error **errp)
>> +{
>> + if (bdrv_find_dirty_bitmap(bs, name)) {
>> + error_setg(errp, "Bitmap already exists: %s", name);
>> + return false;
>> + }
>> +
>> + return true;
>> +}
>> diff --git a/block/parallels.c b/block/parallels.c
>> index f38dd2309c..a49922c6a7 100644
>> --- a/block/parallels.c
>> +++ b/block/parallels.c
>> @@ -1466,14 +1466,25 @@ fail:
>> static int GRAPH_RDLOCK parallels_inactivate(BlockDriverState *bs)
>> {
>> BDRVParallelsState *s = bs->opaque;
>> + Error *err = NULL;
>> int ret;
>> + parallels_store_persistent_dirty_bitmaps(bs, &err);
>> + if (err != NULL) {
> For me this looks quite odd, indirect check for error. Not good
Will add return value;
>
>> + error_reportf_err(err, "Lost persistent bitmaps during "
>> + "inactivation of node '%s': ",
>> + bdrv_get_device_or_node_name(bs));
>> + }
>> +
>> s->header->inuse = 0;
>> parallels_update_header(bs);
>> /* errors are ignored, so we might as well pass exact=true */
>> - ret = bdrv_truncate(bs->file, s->data_end << BDRV_SECTOR_BITS,
>> true,
>> - PREALLOC_MODE_OFF, 0, NULL);
>> + ret = bdrv_truncate(bs->file, s->data_end << BDRV_SECTOR_BITS,
>> + true, PREALLOC_MODE_OFF, 0, NULL);
>> + if (ret < 0) {
>> + error_report("Failed to truncate image: %s", strerror(-ret));
>> + }
>> return ret;
>> }
>> @@ -1525,6 +1536,7 @@ static BlockDriver bdrv_parallels = {
>> .bdrv_co_pdiscard = parallels_co_pdiscard,
>> .bdrv_co_pwrite_zeroes = parallels_co_pwrite_zeroes,
>> .bdrv_inactivate = parallels_inactivate,
>> + .bdrv_co_can_store_new_dirty_bitmap =
>> parallels_co_can_store_new_dirty_bitmap,
>> };
>> static void bdrv_parallels_init(void)
>> diff --git a/block/parallels.h b/block/parallels.h
>> index 493c89e976..9db4f5c908 100644
>> --- a/block/parallels.h
>> +++ b/block/parallels.h
>> @@ -101,5 +101,10 @@ int64_t GRAPH_RDLOCK
>> parallels_allocate_host_clusters(BlockDriverState *bs,
>> int GRAPH_RDLOCK
>> parallels_read_format_extension(BlockDriverState *bs, int64_t ext_off,
>> Error **errp);
>> +void GRAPH_RDLOCK
>> +parallels_store_persistent_dirty_bitmaps(BlockDriverState *bs, Error
>> **errp);
>> +bool coroutine_fn
>> +parallels_co_can_store_new_dirty_bitmap(BlockDriverState *bs, const
>> char *name,
>> + uint32_t granularity, Error
>> **errp);
>> #endif
>
--
Best regards,
Alexander Ivanov
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