diff options
Diffstat (limited to 'qemu-img.c')
| -rw-r--r-- | qemu-img.c | 24 |
1 files changed, 11 insertions, 13 deletions
diff --git a/qemu-img.c b/qemu-img.c index e9c7b30c91..af3effdec5 100644 --- a/qemu-img.c +++ b/qemu-img.c @@ -2671,14 +2671,16 @@ static void dump_map_entry(OutputFormat output_format, MapEntry *e, } } -static int get_block_status(BlockDriverState *bs, int64_t sector_num, - int nb_sectors, MapEntry *e) +static int get_block_status(BlockDriverState *bs, int64_t offset, + int64_t bytes, MapEntry *e) { int64_t ret; int depth; BlockDriverState *file; bool has_offset; + int nb_sectors = bytes >> BDRV_SECTOR_BITS; + assert(bytes < INT_MAX); /* As an optimization, we could cache the current range of unallocated * clusters in each file of the chain, and avoid querying the same * range repeatedly. @@ -2686,8 +2688,8 @@ static int get_block_status(BlockDriverState *bs, int64_t sector_num, depth = 0; for (;;) { - ret = bdrv_get_block_status(bs, sector_num, nb_sectors, &nb_sectors, - &file); + ret = bdrv_get_block_status(bs, offset >> BDRV_SECTOR_BITS, nb_sectors, + &nb_sectors, &file); if (ret < 0) { return ret; } @@ -2707,7 +2709,7 @@ static int get_block_status(BlockDriverState *bs, int64_t sector_num, has_offset = !!(ret & BDRV_BLOCK_OFFSET_VALID); *e = (MapEntry) { - .start = sector_num * BDRV_SECTOR_SIZE, + .start = offset, .length = nb_sectors * BDRV_SECTOR_SIZE, .data = !!(ret & BDRV_BLOCK_DATA), .zero = !!(ret & BDRV_BLOCK_ZERO), @@ -2837,16 +2839,12 @@ static int img_map(int argc, char **argv) length = blk_getlength(blk); while (curr.start + curr.length < length) { - int64_t nsectors_left; - int64_t sector_num; - int n; - - sector_num = (curr.start + curr.length) >> BDRV_SECTOR_BITS; + int64_t offset = curr.start + curr.length; + int64_t n; /* Probe up to 1 GiB at a time. */ - nsectors_left = DIV_ROUND_UP(length, BDRV_SECTOR_SIZE) - sector_num; - n = MIN(1 << (30 - BDRV_SECTOR_BITS), nsectors_left); - ret = get_block_status(bs, sector_num, n, &next); + n = QEMU_ALIGN_DOWN(MIN(1 << 30, length - offset), BDRV_SECTOR_SIZE); + ret = get_block_status(bs, offset, n, &next); if (ret < 0) { error_report("Could not read file metadata: %s", strerror(-ret)); |