| Message ID | 20230529151503.34006-2-alexander.ivanov@virtuozzo.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | parallels: Add duplication check, repair at open, fix bugs | expand |
On 29.05.23 17:14, Alexander Ivanov wrote: > The BDRVParallelsState structure contains data_end field that is measured > in sectors. In parallels_open() initially this field is set by data_off > field from parallels image header. > > According to the parallels format documentation, data_off field contains > an offset, in sectors, from the start of the file to the start of the > data area. For "WithoutFreeSpace" images: if data_off is zero, the offset > is calculated as the end of the BAT table plus some padding to ensure > sector size alignment. > > The parallels_open() function has code for handling zero value in > data_off, but in the result data_end contains the offset in bytes. > > Replace the alignment to sector size by division by sector size and fix > the comparision with s->header_size. > > Signed-off-by: Alexander Ivanov <alexander.ivanov@virtuozzo.com> > Reviewed-by: Denis V. Lunev <den@openvz.org> > --- > block/parallels.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) Reviewed-by: Hanna Czenczek <hreitz@redhat.com>
diff --git a/block/parallels.c b/block/parallels.c index 7c263d5085..1ec98c722b 100644 --- a/block/parallels.c +++ b/block/parallels.c @@ -861,9 +861,9 @@ static int parallels_open(BlockDriverState *bs, QDict *options, int flags, } s->data_end = le32_to_cpu(ph.data_off); if (s->data_end == 0) { - s->data_end = ROUND_UP(bat_entry_off(s->bat_size), BDRV_SECTOR_SIZE); + s->data_end = DIV_ROUND_UP(size, BDRV_SECTOR_SIZE); } - if (s->data_end < s->header_size) { + if (s->data_end < (s->header_size >> BDRV_SECTOR_BITS)) { /* there is not enough unused space to fit to block align between BAT and actual data. We can't avoid read-modify-write... */ s->header_size = size;