Am 17.01.2014 um 23:39 hat Benoît Canet geschrieben:
> Le Friday 17 Jan 2014 à 15:14:51 (+0100), Kevin Wolf a écrit :
> > This function separates filling the BlockLimits from bdrv_open(), which
> > allows it to call it from other operations which may change the limits
> > (e.g. modifications to the backing file chain or bdrv_reopen)
> >
> > Signed-off-by: Kevin Wolf <kw...@redhat.com>
> > Reviewed-by: Max Reitz <mre...@redhat.com>
> > ---
> > block.c | 19 +++++++++++++++++++
> > block/iscsi.c | 46
> > +++++++++++++++++++++++++++++-----------------
> > block/qcow2.c | 11 ++++++++++-
> > block/qed.c | 11 ++++++++++-
> > block/vmdk.c | 22 ++++++++++++++++++----
> > include/block/block_int.h | 2 ++
> > 6 files changed, 88 insertions(+), 23 deletions(-)
> >
> > diff --git a/block.c b/block.c
> > index 64e7d22..99e69da 100644
> > --- a/block.c
> > +++ b/block.c
> > @@ -479,6 +479,19 @@ int bdrv_create_file(const char* filename,
> > QEMUOptionParameter *options,
> > return ret;
> > }
> >
> > +static int bdrv_refresh_limits(BlockDriverState *bs)
> > +{
> > + BlockDriver *drv = bs->drv;
> > +
> > + memset(&bs->bl, 0, sizeof(bs->bl));
> > +
> > + if (drv && drv->bdrv_refresh_limits) {
> > + return drv->bdrv_refresh_limits(bs);
> > + }
> > +
> > + return 0;
> > +}
> > +
> > /*
> > * Create a uniquely-named empty temporary file.
> > * Return 0 upon success, otherwise a negative errno value.
> > @@ -833,6 +846,8 @@ static int bdrv_open_common(BlockDriverState *bs,
> > BlockDriverState *file,
> > goto free_and_fail;
> > }
> >
> > + bdrv_refresh_limits(bs);
> > +
> > #ifndef _WIN32
> > if (bs->is_temporary) {
> > assert(bs->filename[0] != '\0');
> > @@ -1018,6 +1033,10 @@ int bdrv_open_backing_file(BlockDriverState *bs,
> > QDict *options, Error **errp)
> > }
> > pstrcpy(bs->backing_file, sizeof(bs->backing_file),
> > bs->backing_hd->file->filename);
> > +
> > + /* Recalculate the BlockLimits with the backing file */
> > + bdrv_refresh_limits(bs);
> > +
> > return 0;
> > }
> >
> > diff --git a/block/iscsi.c b/block/iscsi.c
> > index c0ea0c4..3202dc5 100644
> > --- a/block/iscsi.c
> > +++ b/block/iscsi.c
> > @@ -1265,23 +1265,6 @@ static int iscsi_open(BlockDriverState *bs, QDict
> > *options, int flags,
> > sizeof(struct scsi_inquiry_block_limits));
> > scsi_free_scsi_task(task);
> > task = NULL;
> > -
> > - if (iscsilun->bl.max_unmap < 0xffffffff) {
> > - bs->bl.max_discard = sector_lun2qemu(iscsilun->bl.max_unmap,
> > - iscsilun);
> > - }
> > - bs->bl.discard_alignment =
> > sector_lun2qemu(iscsilun->bl.opt_unmap_gran,
> > - iscsilun);
> > -
> > - if (iscsilun->bl.max_ws_len < 0xffffffff) {
> > - bs->bl.max_write_zeroes =
> > sector_lun2qemu(iscsilun->bl.max_ws_len,
> > - iscsilun);
> > - }
> > - bs->bl.write_zeroes_alignment =
> > sector_lun2qemu(iscsilun->bl.opt_unmap_gran,
> > - iscsilun);
> > -
> > - bs->bl.opt_transfer_length =
> > sector_lun2qemu(iscsilun->bl.opt_xfer_len,
> > - iscsilun);
> > }
> >
> > #if defined(LIBISCSI_FEATURE_NOP_COUNTER)
> > @@ -1326,6 +1309,34 @@ static void iscsi_close(BlockDriverState *bs)
> > memset(iscsilun, 0, sizeof(IscsiLun));
> > }
> >
> > +static int iscsi_refresh_limits(BlockDriverState *bs)
> > +{
> > + IscsiLun *iscsilun = bs->opaque;
> > +
> > + /* We don't actually refresh here, but just return data queried in
> > + * iscsi_open(): iscsi targets don't change their limits. */
> > + if (iscsilun->lbp.lbpu || iscsilun->lbp.lbpws) {
> > + if (iscsilun->bl.max_unmap < 0xffffffff) {
> > + bs->bl.max_discard = sector_lun2qemu(iscsilun->bl.max_unmap,
> > + iscsilun);
> > + }
> > + bs->bl.discard_alignment =
> > sector_lun2qemu(iscsilun->bl.opt_unmap_gran,
> > + iscsilun);
> > +
> > + if (iscsilun->bl.max_ws_len < 0xffffffff) {
> > + bs->bl.max_write_zeroes =
> > sector_lun2qemu(iscsilun->bl.max_ws_len,
> > + iscsilun);
> > + }
> > + bs->bl.write_zeroes_alignment =
> > sector_lun2qemu(iscsilun->bl.opt_unmap_gran,
> > + iscsilun);
> > +
> > + bs->bl.opt_transfer_length =
> > sector_lun2qemu(iscsilun->bl.opt_xfer_len,
> > + iscsilun);
> Why is bl.opt_transfer_length filled only inside the test for unmap and write
> same ?
> Is there a relationship ?
Good question. The only thing I can say is that I'm moving existing code
here, so this aspect doesnt' change. I suspect this needs a fix on top
of this series. Peter?
Kevin
