On Sun, Aug 19, 2012 at 7:57 AM, Paolo Bonzini <pbonz...@redhat.com> wrote: > Il 17/08/2012 04:36, Ronnie Sahlberg ha scritto: >> The number of blocks of the device is used to compute the device size >> in bdrv_getlength()/iscsi_getlength(). >> For MMC devices, the ReturnedLogicalBlockAddress in the READCAPACITY10 >> has a special meaning when it is 0. >> In this case it does not mean that LBA 0 is the last accessible LBA, >> and thus the device has 1 readable block, but instead it means that the >> disc is blank and there are no readable blocks. >> >> This change ensures that when the iSCSI LUN is loaded with a blank >> DVD-R disk or similar that bdrv_getlength() will return the correct >> size of the device as 0 bytes. >> >> Signed-off-by: Ronnie Sahlberg <ronniesahlb...@gmail.com> >> --- >> block/iscsi.c | 7 ++++++- >> 1 files changed, 6 insertions(+), 1 deletions(-) >> >> diff --git a/block/iscsi.c b/block/iscsi.c >> index bb9cf82..fb420ea 100644 >> --- a/block/iscsi.c >> +++ b/block/iscsi.c >> @@ -717,7 +717,12 @@ iscsi_readcapacity10_cb(struct iscsi_context *iscsi, >> int status, >> } >> >> itask->iscsilun->block_size = rc10->block_size; >> - itask->iscsilun->num_blocks = rc10->lba + 1; >> + if (rc10->lba == 0) { >> + /* blank disk loaded */ >> + itask->iscsilun->num_blocks = 0; >> + } else { >> + itask->iscsilun->num_blocks = rc10->lba + 1; >> + } >> itask->bs->total_sectors = itask->iscsilun->num_blocks * >> itask->iscsilun->block_size / >> BDRV_SECTOR_SIZE ; >> >> > > Thanks, applied to SCSI branch. We'll see whether this hits 1.2.
This patch only matters for the use case of having empty/blank media loaded into an iscsi cdrom. I doubt being able to "burn" data to an iscsi drive is very important or urgent, so it is fine with me to delay until post 1.2 regards ronnie sahlberg