Commit 5696c6e3 authored by Kevin Wolf's avatar Kevin Wolf
Browse files

block: Use BlockBackend for image probing 



This fixes the use of a parent-less BdrvChild in bdrv_open_inherit() by
converting it into a BlockBackend. Which is exactly what it should be,
image probing is an external, standalone user of a node. The requests
can't be considered to originate from the format driver node because
that one isn't even opened yet.

Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
Reviewed-by: default avatarMax Reitz <mreitz@redhat.com>
parent 2d6b86af

block.c

+19 −17
Original line number Diff line number Diff line
@@ -588,21 +588,20 @@ BlockDriver *bdrv_probe_all(const uint8_t *buf, int buf_size, 
    return drv;

}



static int find_image_format(BdrvChild *file, const char *filename,

static int find_image_format(BlockBackend *file, const char *filename,

                             BlockDriver **pdrv, Error **errp)

{

    BlockDriverState *bs = file->bs;

    BlockDriver *drv;

    uint8_t buf[BLOCK_PROBE_BUF_SIZE];

    int ret = 0;



    /* Return the raw BlockDriver * to scsi-generic devices or empty drives */

    if (bdrv_is_sg(bs) || !bdrv_is_inserted(bs) || bdrv_getlength(bs) == 0) {

    if (blk_is_sg(file) || !blk_is_inserted(file) || blk_getlength(file) == 0) {

        *pdrv = &bdrv_raw;

        return ret;

    }



    ret = bdrv_pread(file, 0, buf, sizeof(buf));

    ret = blk_pread(file, 0, buf, sizeof(buf));

    if (ret < 0) {

        error_setg_errno(errp, -ret, "Could not read image for determining its "

                         "format");
@@ -974,7 +973,7 @@ QemuOptsList bdrv_runtime_opts = { 
 *

 * Removes all processed options from *options.

 */

static int bdrv_open_common(BlockDriverState *bs, BdrvChild *file,

static int bdrv_open_common(BlockDriverState *bs, BlockBackend *file,

                            QDict *options, Error **errp)

{

    int ret, open_flags;
@@ -1005,7 +1004,7 @@ static int bdrv_open_common(BlockDriverState *bs, BdrvChild *file, 
    assert(drv != NULL);



    if (file != NULL) {

        filename = file->bs->filename;

        filename = blk_bs(file)->filename;

    } else {

        filename = qdict_get_try_str(options, "filename");

    }
@@ -1707,7 +1706,7 @@ static BlockDriverState *bdrv_open_inherit(const char *filename, 
                                           Error **errp)

{

    int ret;

    BdrvChild *file = NULL;

    BlockBackend *file = NULL;

    BlockDriverState *bs;

    BlockDriver *drv = NULL;

    const char *drvname;
@@ -1805,19 +1804,24 @@ static BlockDriverState *bdrv_open_inherit(const char *filename, 
        qdict_del(options, "backing");

    }



    /* Open image file without format layer. This BdrvChild is only used for

    /* Open image file without format layer. This BlockBackend is only used for

     * probing, the block drivers will do their own bdrv_open_child() for the

     * same BDS, which is why we put the node name back into options. */

    if ((flags & BDRV_O_PROTOCOL) == 0) {

        /* FIXME Shouldn't attach a child to a node that isn't opened yet. */

        file = bdrv_open_child(filename, options, "file", bs,

        BlockDriverState *file_bs;



        file_bs = bdrv_open_child_bs(filename, options, "file", bs,

                                     &child_file, true, &local_err);

        if (local_err) {

            goto fail;

        }

        if (file != NULL) {

        if (file_bs != NULL) {

            file = blk_new();

            blk_insert_bs(file, file_bs);

            bdrv_unref(file_bs);



            qdict_put(options, "file",

                      qstring_from_str(bdrv_get_node_name(file->bs)));

                      qstring_from_str(bdrv_get_node_name(file_bs)));

        }

    }
@@ -1859,7 +1863,7 @@ static BlockDriverState *bdrv_open_inherit(const char *filename, 
    }



    if (file) {

        bdrv_unref_child(bs, file);

        blk_unref(file);

        file = NULL;

    }
@@ -1921,9 +1925,7 @@ static BlockDriverState *bdrv_open_inherit(const char *filename, 
    return bs;



fail:

    if (file != NULL) {

        bdrv_unref_child(bs, file);

    }

    blk_unref(file);

    if (bs->file != NULL) {

        bdrv_unref_child(bs, bs->file);

    }