Commit 9b890bdc authored by Kevin Wolf's avatar Kevin Wolf
Browse files

qcow2: Store data file name in the image 



Rather than requiring that the external data file node is passed
explicitly when creating the qcow2 node, store the filename in the
designated header extension during .bdrv_create and read it from there
as a default during .bdrv_open.

Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent dcc98687

block/qcow2.c

+93 −1
Original line number Diff line number Diff line
@@ -398,6 +398,21 @@ static int qcow2_read_extensions(BlockDriverState *bs, uint64_t start_offset, 
#endif

            break;



        case QCOW2_EXT_MAGIC_DATA_FILE:

        {

            s->image_data_file = g_malloc0(ext.len + 1);

            ret = bdrv_pread(bs->file, offset, s->image_data_file, ext.len);

            if (ret < 0) {

                error_setg_errno(errp, -ret,

                                 "ERROR: Could not read data file name");

                return ret;

            }

#ifdef DEBUG_EXT

            printf("Qcow2: Got external data file %s\n", s->image_data_file);

#endif

            break;

        }



        default:

            /* unknown magic - save it in case we need to rewrite the header */

            /* If you add a new feature, make sure to also update the fast
@@ -1463,6 +1478,15 @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options, 
    }



    if (s->incompatible_features & QCOW2_INCOMPAT_DATA_FILE) {

        if (!s->data_file && s->image_data_file) {

            s->data_file = bdrv_open_child(s->image_data_file, options,

                                           "data-file", bs, &child_file,

                                           false, errp);

            if (!s->data_file) {

                ret = -EINVAL;

                goto fail;

            }

        }

        if (!s->data_file) {

            error_setg(errp, "'data-file' is required for this image");

            ret = -EINVAL;
@@ -1650,6 +1674,7 @@ static int coroutine_fn qcow2_do_open(BlockDriverState *bs, QDict *options, 
    return ret;



 fail:

    g_free(s->image_data_file);

    if (has_data_file(bs)) {

        bdrv_unref_child(bs, s->data_file);

    }
@@ -2269,6 +2294,7 @@ static void qcow2_close(BlockDriverState *bs) 
    g_free(s->unknown_header_fields);

    cleanup_unknown_header_ext(bs);



    g_free(s->image_data_file);

    g_free(s->image_backing_file);

    g_free(s->image_backing_format);
@@ -2445,6 +2471,19 @@ int qcow2_update_header(BlockDriverState *bs) 
        buflen -= ret;

    }



    /* External data file header extension */

    if (has_data_file(bs) && s->image_data_file) {

        ret = header_ext_add(buf, QCOW2_EXT_MAGIC_DATA_FILE,

                             s->image_data_file, strlen(s->image_data_file),

                             buflen);

        if (ret < 0) {

            goto fail;

        }



        buf += ret;

        buflen -= ret;

    }



    /* Full disk encryption header pointer extension */

    if (s->crypto_header.offset != 0) {

        s->crypto_header.offset = cpu_to_be64(s->crypto_header.offset);
@@ -3086,6 +3125,12 @@ qcow2_co_create(BlockdevCreateOptions *create_options, Error **errp) 
        abort();

    }



    /* Set the external data file if necessary */

    if (data_bs) {

        BDRVQcow2State *s = blk_bs(blk)->opaque;

        s->image_data_file = g_strdup(data_bs->filename);

    }



    /* Create a full header (including things like feature table) */

    ret = qcow2_update_header(blk_bs(blk));

    if (ret < 0) {
@@ -3165,6 +3210,7 @@ static int coroutine_fn qcow2_co_create_opts(const char *filename, QemuOpts *opt 
    QDict *qdict;

    Visitor *v;

    BlockDriverState *bs = NULL;

    BlockDriverState *data_bs = NULL;

    Error *local_err = NULL;

    const char *val;

    int ret;
@@ -3228,6 +3274,26 @@ static int coroutine_fn qcow2_co_create_opts(const char *filename, QemuOpts *opt 
        goto finish;

    }



    /* Create and open an external data file (protocol layer) */

    val = qdict_get_try_str(qdict, BLOCK_OPT_DATA_FILE);

    if (val) {

        ret = bdrv_create_file(val, opts, errp);

        if (ret < 0) {

            goto finish;

        }



        data_bs = bdrv_open(val, NULL, NULL,

                            BDRV_O_RDWR | BDRV_O_RESIZE | BDRV_O_PROTOCOL,

                            errp);

        if (data_bs == NULL) {

            ret = -EIO;

            goto finish;

        }



        qdict_del(qdict, BLOCK_OPT_DATA_FILE);

        qdict_put_str(qdict, "data-file", data_bs->node_name);

    }



    /* Set 'driver' and 'node' options */

    qdict_put_str(qdict, "driver", "qcow2");

    qdict_put_str(qdict, "file", bs->node_name);
@@ -3262,6 +3328,7 @@ static int coroutine_fn qcow2_co_create_opts(const char *filename, QemuOpts *opt 
finish:

    qobject_unref(qdict);

    bdrv_unref(bs);

    bdrv_unref(data_bs);

    qapi_free_BlockdevCreateOptions(create_options);

    return ret;

}
@@ -4552,6 +4619,8 @@ static ImageInfoSpecific *qcow2_get_specific_info(BlockDriverState *bs, 
            .refcount_bits      = s->refcount_bits,

            .has_bitmaps        = !!bitmaps,

            .bitmaps            = bitmaps,

            .has_data_file      = !!s->image_data_file,

            .data_file          = g_strdup(s->image_data_file),

        };

    } else {

        /* if this assertion fails, this probably means a new version was
@@ -4754,7 +4823,7 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, 
    BDRVQcow2State *s = bs->opaque;

    int old_version = s->qcow_version, new_version = old_version;

    uint64_t new_size = 0;

    const char *backing_file = NULL, *backing_format = NULL;

    const char *backing_file = NULL, *backing_format = NULL, *data_file = NULL;

    bool lazy_refcounts = s->use_lazy_refcounts;

    const char *compat = NULL;

    uint64_t cluster_size = s->cluster_size;
@@ -4836,6 +4905,13 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, 
                           "may not exceed 64 bits");

                return -EINVAL;

            }

        } else if (!strcmp(desc->name, BLOCK_OPT_DATA_FILE)) {

            data_file = qemu_opt_get(opts, BLOCK_OPT_DATA_FILE);

            if (data_file && !has_data_file(bs)) {

                error_setg(errp, "data-file can only be set for images that "

                                 "use an external data file");

                return -EINVAL;

            }

        } else {

            /* if this point is reached, this probably means a new option was

             * added without having it covered here */
@@ -4882,6 +4958,17 @@ static int qcow2_amend_options(BlockDriverState *bs, QemuOpts *opts, 
        }

    }



    if (data_file) {

        g_free(s->image_data_file);

        s->image_data_file = *data_file ? g_strdup(data_file) : NULL;

    }



    ret = qcow2_update_header(bs);

    if (ret < 0) {

        error_setg_errno(errp, -ret, "Failed to update the image header");

        return ret;

    }



    if (backing_file || backing_format) {

        ret = qcow2_change_backing_file(bs,

                    backing_file ?: s->image_backing_file,
@@ -5029,6 +5116,11 @@ static QemuOptsList qcow2_create_opts = { 
            .type = QEMU_OPT_STRING,

            .help = "Image format of the base image"

        },

        {

            .name = BLOCK_OPT_DATA_FILE,

            .type = QEMU_OPT_STRING,

            .help = "File name of an external data file"

        },

        {

            .name = BLOCK_OPT_ENCRYPT,

            .type = QEMU_OPT_BOOL,

block/qcow2.h

+1 −0
Original line number Diff line number Diff line
@@ -343,6 +343,7 @@ typedef struct BDRVQcow2State { 
     * override) */

    char *image_backing_file;

    char *image_backing_format;

    char *image_data_file;



    CoQueue compress_wait_queue;

    int nb_compress_threads;

qapi/block-core.json

+7 −1
Original line number Diff line number Diff line
@@ -59,6 +59,9 @@ 
#

# @compat: compatibility level

#

# @data-file: the filename of the external data file that is stored in the

#             image and used as a default for opening the image (since: 4.0)

#

# @lazy-refcounts: on or off; only valid for compat >= 1.1

#

# @corrupt: true if the image has been marked corrupt; only valid for
@@ -76,6 +79,7 @@ 
{ 'struct': 'ImageInfoSpecificQCow2',

  'data': {

      'compat': 'str',

      '*data-file': 'str',

      '*lazy-refcounts': 'bool',

      '*corrupt': 'bool',

      'refcount-bits': 'int',
@@ -3082,7 +3086,9 @@ 
#

# @data-file:             reference to or definition of the external data file.

#                         This may only be specified for images that require an

#                         external data file. (since 4.0)

#                         external data file. If it is not specified for such

#                         an image, the data file name is loaded from the image

#                         file. (since 4.0)

#

# Since: 2.9

##

tests/qemu-iotests/082.out

+27 −0
Original line number Diff line number Diff line
@@ -48,6 +48,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -69,6 +70,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -90,6 +92,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -111,6 +114,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -132,6 +136,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -153,6 +158,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -174,6 +180,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -195,6 +202,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -231,6 +239,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -304,6 +313,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -325,6 +335,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -346,6 +357,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -367,6 +379,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -388,6 +401,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -409,6 +423,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -430,6 +445,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -451,6 +467,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -487,6 +504,7 @@ Supported options: 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -568,6 +586,7 @@ Creation options for 'qcow2': 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -590,6 +609,7 @@ Creation options for 'qcow2': 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -612,6 +632,7 @@ Creation options for 'qcow2': 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -634,6 +655,7 @@ Creation options for 'qcow2': 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -656,6 +678,7 @@ Creation options for 'qcow2': 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -678,6 +701,7 @@ Creation options for 'qcow2': 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -700,6 +724,7 @@ Creation options for 'qcow2': 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -722,6 +747,7 @@ Creation options for 'qcow2': 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'
@@ -761,6 +787,7 @@ Creation options for 'qcow2': 
  backing_fmt=<str>      - Image format of the base image

  cluster_size=<size>    - qcow2 cluster size

  compat=<str>           - Compatibility level (0.10 or 1.1)

  data_file=<str>        - File name of an external data file

  encrypt.cipher-alg=<str> - Name of encryption cipher algorithm

  encrypt.cipher-mode=<str> - Name of encryption cipher mode

  encrypt.format=<str>   - Encrypt the image, format choices: 'aes', 'luks'