diff options
| -rw-r--r-- | block/vpc.c | 50 |
1 files changed, 48 insertions, 2 deletions
diff --git a/block/vpc.c b/block/vpc.c index 7fddbf0b75..1533b6a64d 100644 --- a/block/vpc.c +++ b/block/vpc.c @@ -597,6 +597,51 @@ static coroutine_fn int vpc_co_write(BlockDriverState *bs, int64_t sector_num, return ret; } +static int64_t coroutine_fn vpc_co_get_block_status(BlockDriverState *bs, + int64_t sector_num, int nb_sectors, int *pnum) +{ + BDRVVPCState *s = bs->opaque; + VHDFooter *footer = (VHDFooter*) s->footer_buf; + int64_t start, offset, next; + bool allocated; + int n; + + if (be32_to_cpu(footer->type) == VHD_FIXED) { + *pnum = nb_sectors; + return BDRV_BLOCK_RAW | BDRV_BLOCK_OFFSET_VALID | BDRV_BLOCK_DATA | + (sector_num << BDRV_SECTOR_BITS); + } + + offset = get_sector_offset(bs, sector_num, 0); + start = offset; + allocated = (offset != -1); + *pnum = 0; + + do { + /* All sectors in a block are contiguous (without using the bitmap) */ + n = ROUND_UP(sector_num + 1, s->block_size / BDRV_SECTOR_SIZE) + - sector_num; + n = MIN(n, nb_sectors); + + *pnum += n; + sector_num += n; + nb_sectors -= n; + next = start + (*pnum * BDRV_SECTOR_SIZE); + + if (nb_sectors == 0) { + break; + } + + offset = get_sector_offset(bs, sector_num, 0); + } while ((allocated && offset == next) || (!allocated && offset == -1)); + + if (allocated) { + return BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID | start; + } else { + return 0; + } +} + /* * Calculates the number of cylinders, heads and sectors per cylinder * based on a given number of sectors. This is the algorithm described @@ -903,8 +948,9 @@ static BlockDriver bdrv_vpc = { .bdrv_reopen_prepare = vpc_reopen_prepare, .bdrv_create = vpc_create, - .bdrv_read = vpc_co_read, - .bdrv_write = vpc_co_write, + .bdrv_read = vpc_co_read, + .bdrv_write = vpc_co_write, + .bdrv_co_get_block_status = vpc_co_get_block_status, .bdrv_get_info = vpc_get_info, |