On Wed, May 20, 2020 at 10:57:00AM +0200, Philippe Mathieu-Daudé wrote:
> On 5/20/20 10:06 AM, Roman Kagan wrote:
> > Several block device properties related to blocksize configuration must
> > be in certain relationship WRT each other: physical block must be no
> > smaller than logical block; min_io_size, opt_io_size, and
> > discard_granularity must be a multiple of a logical block.
> >
> > To ensure these requirements are met, add corresponding consistency
> > checks to blkconf_blocksizes, adjusting its signature to communicate
> > possible error to the caller. Also remove the now redundant consistency
> > checks from the specific devices.
> >
> > Signed-off-by: Roman Kagan <rvka...@yandex-team.ru>
> > ---
> > v4: new patch
> >
> > include/hw/block/block.h | 2 +-
> > hw/block/block.c | 29 ++++++++++++++++++++++++++++-
> > hw/block/fdc.c | 5 ++++-
> > hw/block/nvme.c | 5 ++++-
> > hw/block/virtio-blk.c | 7 +------
> > hw/ide/qdev.c | 5 ++++-
> > hw/scsi/scsi-disk.c | 10 +++-------
> > hw/usb/dev-storage.c | 5 ++++-
> > tests/qemu-iotests/172.out | 2 +-
> > 9 files changed, 50 insertions(+), 20 deletions(-)
> >
> > diff --git a/include/hw/block/block.h b/include/hw/block/block.h
> > index d7246f3862..784953a237 100644
> > --- a/include/hw/block/block.h
> > +++ b/include/hw/block/block.h
> > @@ -87,7 +87,7 @@ bool blk_check_size_and_read_all(BlockBackend *blk, void
> > *buf, hwaddr size,
> > bool blkconf_geometry(BlockConf *conf, int *trans,
> > unsigned cyls_max, unsigned heads_max, unsigned
> > secs_max,
> > Error **errp);
> > -void blkconf_blocksizes(BlockConf *conf);
> > +bool blkconf_blocksizes(BlockConf *conf, Error **errp);
> > bool blkconf_apply_backend_options(BlockConf *conf, bool readonly,
> > bool resizable, Error **errp);
> > diff --git a/hw/block/block.c b/hw/block/block.c
> > index bf56c7612b..5f8ebff59c 100644
> > --- a/hw/block/block.c
> > +++ b/hw/block/block.c
> > @@ -61,7 +61,7 @@ bool blk_check_size_and_read_all(BlockBackend *blk, void
> > *buf, hwaddr size,
> > return true;
> > }
> > -void blkconf_blocksizes(BlockConf *conf)
> > +bool blkconf_blocksizes(BlockConf *conf, Error **errp)
> > {
> > BlockBackend *blk = conf->blk;
> > BlockSizes blocksizes;
> > @@ -83,6 +83,33 @@ void blkconf_blocksizes(BlockConf *conf)
> > conf->logical_block_size = BDRV_SECTOR_SIZE;
> > }
> > }
> > +
> > + if (conf->logical_block_size > conf->physical_block_size) {
> > + error_setg(errp,
> > + "logical_block_size > physical_block_size not
> > supported");
>
> "not supported" or "invalid"?
>
> > + return false;
> > + }
> > +
> > + if (conf->min_io_size % conf->logical_block_size) {
>
> It seems the block code usually do:
>
> if (!QEMU_IS_ALIGNED(conf->min_io_size, conf->logical_block_size)) {
>
> > + error_setg(errp,
> > + "min_io_size must be a multple of logical_block_size");
>
> Typo "multple" -> "multiple".
>
> > + return false;
> > + }
> > +
> > + if (conf->opt_io_size % conf->logical_block_size) {
> > + error_setg(errp,
> > + "opt_io_size must be a multple of logical_block_size");
>
> Ditto.
>
> > + return false;
> > + }
> > +
> > + if (conf->discard_granularity != -1 &&
> > + conf->discard_granularity % conf->logical_block_size) {
> > + error_setg(errp, "discard_granularity must be "
> > + "a multple of logical_block_size");
>
> Again.
>
> > + return false;
> > + }
> > +
> > + return true;
>
> Usually we return true for error, isn't it?
I just followed the convention of all other functions with error
handling in this file.
> > }
> > bool blkconf_apply_backend_options(BlockConf *conf, bool readonly,
> > diff --git a/hw/block/fdc.c b/hw/block/fdc.c
> > index c5fb9d6ece..8eda572ef4 100644
> > --- a/hw/block/fdc.c
> > +++ b/hw/block/fdc.c
> > @@ -554,7 +554,10 @@ static void floppy_drive_realize(DeviceState *qdev,
> > Error **errp)
> > read_only = !blk_bs(dev->conf.blk) ||
> > blk_is_read_only(dev->conf.blk);
> > }
> > - blkconf_blocksizes(&dev->conf);
> > + if (!blkconf_blocksizes(&dev->conf, errp)) {
> > + return;
> > + }
> > +
> > if (dev->conf.logical_block_size != 512 ||
> > dev->conf.physical_block_size != 512)
> > {
> > diff --git a/hw/block/nvme.c b/hw/block/nvme.c
> > index 2f3100e56c..672650e162 100644
> > --- a/hw/block/nvme.c
> > +++ b/hw/block/nvme.c
> > @@ -1390,7 +1390,10 @@ static void nvme_realize(PCIDevice *pci_dev, Error
> > **errp)
> > host_memory_backend_set_mapped(n->pmrdev, true);
> > }
> > - blkconf_blocksizes(&n->conf);
> > + if (!blkconf_blocksizes(&n->conf, errp)) {
> > + return;
> > + }
> > +
> > if (!blkconf_apply_backend_options(&n->conf,
> > blk_is_read_only(n->conf.blk),
> > false, errp)) {
> > return;
> > diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
> > index 413083e62f..4ffdb130be 100644
> > --- a/hw/block/virtio-blk.c
> > +++ b/hw/block/virtio-blk.c
> > @@ -1162,12 +1162,7 @@ static void virtio_blk_device_realize(DeviceState
> > *dev, Error **errp)
> > return;
> > }
> > - blkconf_blocksizes(&conf->conf);
> > -
> > - if (conf->conf.logical_block_size >
> > - conf->conf.physical_block_size) {
> > - error_setg(errp,
> > - "logical_block_size > physical_block_size not
> > supported");
>
> Ah, "not supported" comes from here, OK.
Indeed :)
>
> > + if (!blkconf_blocksizes(&conf->conf, errp)) {
> > return;
> > }
> > diff --git a/hw/ide/qdev.c b/hw/ide/qdev.c
> > index 06b11583f5..b4821b2403 100644
> > --- a/hw/ide/qdev.c
> > +++ b/hw/ide/qdev.c
> > @@ -187,7 +187,10 @@ static void ide_dev_initfn(IDEDevice *dev,
> > IDEDriveKind kind, Error **errp)
> > return;
> > }
> > - blkconf_blocksizes(&dev->conf);
> > + if (!blkconf_blocksizes(&dev->conf, errp)) {
> > + return;
> > + }
> > +
> > if (dev->conf.logical_block_size != 512) {
> > error_setg(errp, "logical_block_size must be 512 for IDE");
> > return;
> > diff --git a/hw/scsi/scsi-disk.c b/hw/scsi/scsi-disk.c
> > index 387503e11b..06c8f1ba92 100644
> > --- a/hw/scsi/scsi-disk.c
> > +++ b/hw/scsi/scsi-disk.c
> > @@ -2346,12 +2346,7 @@ static void scsi_realize(SCSIDevice *dev, Error
> > **errp)
> > return;
> > }
> > - blkconf_blocksizes(&s->qdev.conf);
> > -
> > - if (s->qdev.conf.logical_block_size >
> > - s->qdev.conf.physical_block_size) {
> > - error_setg(errp,
> > - "logical_block_size > physical_block_size not
> > supported");
> > + if (!blkconf_blocksizes(&s->qdev.conf, errp)) {
> > return;
> > }
> > @@ -2436,7 +2431,8 @@ static void scsi_hd_realize(SCSIDevice *dev, Error
> > **errp)
> > if (s->qdev.conf.blk) {
> > ctx = blk_get_aio_context(s->qdev.conf.blk);
> > aio_context_acquire(ctx);
> > - blkconf_blocksizes(&s->qdev.conf);
> > + /* ignore errors, blocksizes will be revalidated in scsi_realize */
> > + blkconf_blocksizes(&s->qdev.conf, NULL);
>
> Hmm, why not bail out ASAP on error?
You're probably right, it'll be cleaner this way.
Thanks,
Roman.
>
> Good cleanup otherwise.
>
> > }
> > s->qdev.blocksize = s->qdev.conf.logical_block_size;
> > s->qdev.type = TYPE_DISK;
> > diff --git a/hw/usb/dev-storage.c b/hw/usb/dev-storage.c
> > index 4eba47538d..de461f37bd 100644
> > --- a/hw/usb/dev-storage.c
> > +++ b/hw/usb/dev-storage.c
> > @@ -599,7 +599,10 @@ static void usb_msd_storage_realize(USBDevice *dev,
> > Error **errp)
> > return;
> > }
> > - blkconf_blocksizes(&s->conf);
> > + if (!blkconf_blocksizes(&s->conf, errp)) {
> > + return;
> > + }
> > +
> > if (!blkconf_apply_backend_options(&s->conf, blk_is_read_only(blk),
> > true,
> > errp)) {
> > return;
> > diff --git a/tests/qemu-iotests/172.out b/tests/qemu-iotests/172.out
> > index 7abbe82427..59cc70aebb 100644
> > --- a/tests/qemu-iotests/172.out
> > +++ b/tests/qemu-iotests/172.out
> > @@ -1204,7 +1204,7 @@ Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device
> > floppy,drive=none0,physica
> > drive-type = "144"
> > Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device
> > floppy,drive=none0,logical_block_size=4096
> > -QEMU_PROG: -device floppy,drive=none0,logical_block_size=4096: Physical
> > and logical block size must be 512 for floppy
> > +QEMU_PROG: -device floppy,drive=none0,logical_block_size=4096:
> > logical_block_size > physical_block_size not supported
> > Testing: -drive if=none,file=TEST_DIR/t.qcow2 -device
> > floppy,drive=none0,physical_block_size=1024
> > QEMU_PROG: -device floppy,drive=none0,physical_block_size=1024: Physical
> > and logical block size must be 512 for floppy
> >
>
