Commit b8968c87 authored by Andrey Shinkevich's avatar Andrey Shinkevich Committed by Eric Blake
Browse files

qcow2: Add list of bitmaps to ImageInfoSpecificQCow2 



In the 'Format specific information' section of the 'qemu-img info'
command output, the supplemental information about existing QCOW2
bitmaps will be shown, such as a bitmap name, flags and granularity:

image: /vz/vmprivate/VM1/harddisk.hdd
file format: qcow2
virtual size: 64G (68719476736 bytes)
disk size: 3.0M
cluster_size: 1048576
Format specific information:
    compat: 1.1
    lazy refcounts: true
    bitmaps:
        [0]:
            flags:
                [0]: in-use
                [1]: auto
            name: back-up1
            granularity: 65536
        [1]:
            flags:
                [0]: in-use
                [1]: auto
            name: back-up2
            granularity: 65536
    refcount bits: 16
    corrupt: false

Signed-off-by: default avatarAndrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Reviewed-by: default avatarEric Blake <eblake@redhat.com>
Reviewed-by: default avatarVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <1549638368-530182-3-git-send-email-andrey.shinkevich@virtuozzo.com>
Signed-off-by: default avatarEric Blake <eblake@redhat.com>
parent 1bf6e9ca

block/qcow2-bitmap.c

+76 −0
Original line number Diff line number Diff line
@@ -1006,6 +1006,82 @@ fail: 
    return false;

}





static Qcow2BitmapInfoFlagsList *get_bitmap_info_flags(uint32_t flags)

{

    Qcow2BitmapInfoFlagsList *list = NULL;

    Qcow2BitmapInfoFlagsList **plist = &list;

    int i;



    static const struct {

        int bme;  /* Bitmap directory entry flags */

        int info; /* The flags to report to the user */

    } map[] = {

        { BME_FLAG_IN_USE, QCOW2_BITMAP_INFO_FLAGS_IN_USE },

        { BME_FLAG_AUTO,   QCOW2_BITMAP_INFO_FLAGS_AUTO },

    };



    int map_size = ARRAY_SIZE(map);



    for (i = 0; i < map_size; ++i) {

        if (flags & map[i].bme) {

            Qcow2BitmapInfoFlagsList *entry =

                g_new0(Qcow2BitmapInfoFlagsList, 1);

            entry->value = map[i].info;

            *plist = entry;

            plist = &entry->next;

            flags &= ~map[i].bme;

        }

    }

    /* Check if the BME_* mapping above is complete */

    assert(!flags);



    return list;

}



/*

 * qcow2_get_bitmap_info_list()

 * Returns a list of QCOW2 bitmap details.

 * In case of no bitmaps, the function returns NULL and

 * the @errp parameter is not set.

 * When bitmap information can not be obtained, the function returns

 * NULL and the @errp parameter is set.

 */

Qcow2BitmapInfoList *qcow2_get_bitmap_info_list(BlockDriverState *bs,

                                                Error **errp)

{

    BDRVQcow2State *s = bs->opaque;

    Qcow2BitmapList *bm_list;

    Qcow2Bitmap *bm;

    Qcow2BitmapInfoList *list = NULL;

    Qcow2BitmapInfoList **plist = &list;



    if (s->nb_bitmaps == 0) {

        return NULL;

    }



    bm_list = bitmap_list_load(bs, s->bitmap_directory_offset,

                               s->bitmap_directory_size, errp);

    if (bm_list == NULL) {

        return NULL;

    }



    QSIMPLEQ_FOREACH(bm, bm_list, entry) {

        Qcow2BitmapInfo *info = g_new0(Qcow2BitmapInfo, 1);

        Qcow2BitmapInfoList *obj = g_new0(Qcow2BitmapInfoList, 1);

        info->granularity = 1U << bm->granularity_bits;

        info->name = g_strdup(bm->name);

        info->flags = get_bitmap_info_flags(bm->flags & ~BME_RESERVED_FLAGS);

        obj->value = info;

        *plist = obj;

        plist = &obj->next;

    }



    bitmap_list_free(bm_list);



    return list;

}



int qcow2_reopen_bitmaps_rw_hint(BlockDriverState *bs, bool *header_updated,

                                 Error **errp)

{

block/qcow2.c

+10 −1
Original line number Diff line number Diff line
@@ -4387,7 +4387,7 @@ static ImageInfoSpecific *qcow2_get_specific_info(BlockDriverState *bs, 
    spec_info = g_new(ImageInfoSpecific, 1);

    *spec_info = (ImageInfoSpecific){

        .type  = IMAGE_INFO_SPECIFIC_KIND_QCOW2,

        .u.qcow2.data = g_new(ImageInfoSpecificQCow2, 1),

        .u.qcow2.data = g_new0(ImageInfoSpecificQCow2, 1),

    };

    if (s->qcow_version == 2) {

        *spec_info->u.qcow2.data = (ImageInfoSpecificQCow2){
@@ -4395,6 +4395,13 @@ static ImageInfoSpecific *qcow2_get_specific_info(BlockDriverState *bs, 
            .refcount_bits      = s->refcount_bits,

        };

    } else if (s->qcow_version == 3) {

        Qcow2BitmapInfoList *bitmaps;

        bitmaps = qcow2_get_bitmap_info_list(bs, &local_err);

        if (local_err) {

            error_propagate(errp, local_err);

            qapi_free_ImageInfoSpecific(spec_info);

            return NULL;

        }

        *spec_info->u.qcow2.data = (ImageInfoSpecificQCow2){

            .compat             = g_strdup("1.1"),

            .lazy_refcounts     = s->compatible_features &
@@ -4404,6 +4411,8 @@ static ImageInfoSpecific *qcow2_get_specific_info(BlockDriverState *bs, 
                                  QCOW2_INCOMPAT_CORRUPT,

            .has_corrupt        = true,

            .refcount_bits      = s->refcount_bits,

            .has_bitmaps        = !!bitmaps,

            .bitmaps            = bitmaps,

        };

    } else {

        /* if this assertion fails, this probably means a new version was

block/qcow2.h

+2 −0
Original line number Diff line number Diff line
@@ -684,6 +684,8 @@ int qcow2_check_bitmaps_refcounts(BlockDriverState *bs, BdrvCheckResult *res, 
                                  void **refcount_table,

                                  int64_t *refcount_table_size);

bool qcow2_load_dirty_bitmaps(BlockDriverState *bs, Error **errp);

Qcow2BitmapInfoList *qcow2_get_bitmap_info_list(BlockDriverState *bs,

                                                Error **errp);

int qcow2_reopen_bitmaps_rw_hint(BlockDriverState *bs, bool *header_updated,

                                 Error **errp);

int qcow2_reopen_bitmaps_rw(BlockDriverState *bs, Error **errp);

qapi/block-core.json

+40 −1
Original line number Diff line number Diff line
@@ -69,6 +69,8 @@ 
# @encrypt: details about encryption parameters; only set if image

#           is encrypted (since 2.10)

#

# @bitmaps: A list of qcow2 bitmap details (since 4.0)

#

# Since: 1.7

##

{ 'struct': 'ImageInfoSpecificQCow2',
@@ -77,7 +79,8 @@ 
      '*lazy-refcounts': 'bool',

      '*corrupt': 'bool',

      'refcount-bits': 'int',

      '*encrypt': 'ImageInfoSpecificQCow2Encryption'

      '*encrypt': 'ImageInfoSpecificQCow2Encryption',

      '*bitmaps': ['Qcow2BitmapInfo']

  } }



##
@@ -453,6 +456,42 @@ 
  'data': {'*name': 'str', 'count': 'int', 'granularity': 'uint32',

           'status': 'DirtyBitmapStatus'} }



##

# @Qcow2BitmapInfoFlags:

#

# An enumeration of flags that a bitmap can report to the user.

#

# @in-use: This flag is set by any process actively modifying the qcow2 file,

#          and cleared when the updated bitmap is flushed to the qcow2 image.

#          The presence of this flag in an offline image means that the bitmap

#          was not saved correctly after its last usage, and may contain

#          inconsistent data.

#

# @auto: The bitmap must reflect all changes of the virtual disk by any

#        application that would write to this qcow2 file.

#

# Since: 4.0

##

{ 'enum': 'Qcow2BitmapInfoFlags',

  'data': ['in-use', 'auto'] }



##

# @Qcow2BitmapInfo:

#

# Qcow2 bitmap information.

#

# @name: the name of the bitmap

#

# @granularity: granularity of the bitmap in bytes

#

# @flags: flags of the bitmap

#

# Since: 4.0

##

{ 'struct': 'Qcow2BitmapInfo',

  'data': {'name': 'str', 'granularity': 'uint32',

           'flags': ['Qcow2BitmapInfoFlags'] } }



##

# @BlockLatencyHistogramInfo:

#