diff options
| -rw-r--r-- | block/vpc.c | 113 |
1 files changed, 82 insertions, 31 deletions
diff --git a/block/vpc.c b/block/vpc.c index 8824211713..28ffa0d2f8 100644 --- a/block/vpc.c +++ b/block/vpc.c @@ -902,6 +902,62 @@ static int create_fixed_disk(BlockBackend *blk, uint8_t *buf, return ret; } +static int calculate_rounded_image_size(BlockdevCreateOptionsVpc *vpc_opts, + uint16_t *out_cyls, + uint8_t *out_heads, + uint8_t *out_secs_per_cyl, + int64_t *out_total_sectors, + Error **errp) +{ + int64_t total_size = vpc_opts->size; + uint16_t cyls = 0; + uint8_t heads = 0; + uint8_t secs_per_cyl = 0; + int64_t total_sectors; + int i; + + /* + * Calculate matching total_size and geometry. Increase the number of + * sectors requested until we get enough (or fail). This ensures that + * qemu-img convert doesn't truncate images, but rather rounds up. + * + * If the image size can't be represented by a spec conformant CHS geometry, + * we set the geometry to 65535 x 16 x 255 (CxHxS) sectors and use + * the image size from the VHD footer to calculate total_sectors. + */ + if (vpc_opts->force_size) { + /* This will force the use of total_size for sector count, below */ + cyls = VHD_CHS_MAX_C; + heads = VHD_CHS_MAX_H; + secs_per_cyl = VHD_CHS_MAX_S; + } else { + total_sectors = MIN(VHD_MAX_GEOMETRY, total_size / BDRV_SECTOR_SIZE); + for (i = 0; total_sectors > (int64_t)cyls * heads * secs_per_cyl; i++) { + calculate_geometry(total_sectors + i, &cyls, &heads, &secs_per_cyl); + } + } + + if ((int64_t)cyls * heads * secs_per_cyl == VHD_MAX_GEOMETRY) { + total_sectors = total_size / BDRV_SECTOR_SIZE; + /* Allow a maximum disk size of 2040 GiB */ + if (total_sectors > VHD_MAX_SECTORS) { + error_setg(errp, "Disk size is too large, max size is 2040 GiB"); + return -EFBIG; + } + } else { + total_sectors = (int64_t) cyls * heads * secs_per_cyl; + } + + *out_total_sectors = total_sectors; + if (out_cyls) { + *out_cyls = cyls; + *out_heads = heads; + *out_secs_per_cyl = secs_per_cyl; + } + + return 0; +} + static int coroutine_fn vpc_co_create(BlockdevCreateOptions *opts, Error **errp) { @@ -911,7 +967,6 @@ static int coroutine_fn vpc_co_create(BlockdevCreateOptions *opts, uint8_t buf[1024]; VHDFooter *footer = (VHDFooter *) buf; - int i; uint16_t cyls = 0; uint8_t heads = 0; uint8_t secs_per_cyl = 0; @@ -953,38 +1008,22 @@ static int coroutine_fn vpc_co_create(BlockdevCreateOptions *opts, } blk_set_allow_write_beyond_eof(blk, true); - /* - * Calculate matching total_size and geometry. Increase the number of - * sectors requested until we get enough (or fail). This ensures that - * qemu-img convert doesn't truncate images, but rather rounds up. - * - * If the image size can't be represented by a spec conformant CHS geometry, - * we set the geometry to 65535 x 16 x 255 (CxHxS) sectors and use - * the image size from the VHD footer to calculate total_sectors. - */ - if (vpc_opts->force_size) { - /* This will force the use of total_size for sector count, below */ - cyls = VHD_CHS_MAX_C; - heads = VHD_CHS_MAX_H; - secs_per_cyl = VHD_CHS_MAX_S; - } else { - total_sectors = MIN(VHD_MAX_GEOMETRY, total_size / BDRV_SECTOR_SIZE); - for (i = 0; total_sectors > (int64_t)cyls * heads * secs_per_cyl; i++) { - calculate_geometry(total_sectors + i, &cyls, &heads, &secs_per_cyl); - } + /* Get geometry and check that it matches the image size*/ + ret = calculate_rounded_image_size(vpc_opts, &cyls, &heads, &secs_per_cyl, + &total_sectors, errp); + if (ret < 0) { + goto out; } - if ((int64_t)cyls * heads * secs_per_cyl == VHD_MAX_GEOMETRY) { - total_sectors = total_size / BDRV_SECTOR_SIZE; - /* Allow a maximum disk size of 2040 GiB */ - if (total_sectors > VHD_MAX_SECTORS) { - error_setg(errp, "Disk size is too large, max size is 2040 GiB"); - ret = -EFBIG; - goto out; - } - } else { - total_sectors = (int64_t)cyls * heads * secs_per_cyl; - total_size = total_sectors * BDRV_SECTOR_SIZE; + if (total_size != total_sectors * BDRV_SECTOR_SIZE) { + error_setg(errp, "The requested image size cannot be represented in " + "CHS geometry"); + error_append_hint(errp, "Try size=%llu or force-size=on (the " + "latter makes the image incompatible with " + "Virtual PC)", + total_sectors * BDRV_SECTOR_SIZE); + ret = -EINVAL; + goto out; } /* Prepare the Hard Disk Footer */ @@ -1102,6 +1141,18 @@ static int coroutine_fn vpc_co_create_opts(const char *filename, create_options->u.vpc.size = ROUND_UP(create_options->u.vpc.size, BDRV_SECTOR_SIZE); + if (!create_options->u.vpc.force_size) { + int64_t total_sectors; + ret = calculate_rounded_image_size(&create_options->u.vpc, NULL, NULL, + NULL, &total_sectors, errp); + if (ret < 0) { + goto fail; + } + + create_options->u.vpc.size = total_sectors * BDRV_SECTOR_SIZE; + } + + /* Create the vpc image (format layer) */ ret = vpc_co_create(create_options, errp); |