Add three new qdev properties to export block topology information to
the guest. This is needed to get optimal I/O alignment for RAID arrays
or SSDs.
The options are:
- physical_block_size to specify the physical block size of the device,
this is going to increase from 512 bytes to 4096 kilobytes for many
modern storage devices
- min_io_size to specify the minimal I/O size without performance impact,
this is typically set to the RAID chunk size for arrays.
- opt_io_size to specify the optimal sustained I/O size, this is
typically the RAID stripe width for arrays.
I decided to not auto-probe these values from blkid which might easily
be possible as I don't know how to deal with these issues on migration.
Note that we specificly only set the physical_block_size, and not the
logial one which is the unit all I/O is described in. The reason for
that is that IDE does not support increasing the logical block size and
at last for now I want to stick to one meachnisms in queue and allow
for easy switching of transports for a given backing image which would
not be possible if scsi and virtio use real 4k sectors, while ide only
uses the physical block exponent.
To make this more common for the different block drivers introduce a
new BlockConf structure holding all common block properties and a
DEFINE_BLOCK_PROPERTIES macro to add them all together, mirroring
what is done for network drivers. Also switch over all block drivers
to use it, except for the floppy driver which has weird driveA/driveB
properties and probably won't require any advanced block options ever.
Example usage for a virtio device with 4k physical block size and
8k optimal I/O size:
-drive file=scratch.img,media=disk,cache=none,id=scratch \
-device virtio-blk-pci,drive=scratch,physical_block_size=4096,opt_io_size=8192
aliguori: updated patch to take into account BLOCK events
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This patch adds a new property named 'ver' to ide-drive which allows to
specify the version which the virtual disk/cdrom should report to the
guest. By default this is the qemu version (i.e. 0.12). usage:
-drive if=none,id=disk,file=...
-device ide-drive,bus=ide.0,unit=0,drive=disk,ver=42
You can also switch the version for all ide drives using:
-global ide-drive.ver=42
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This is a workaround only, and is a partial revert
of a few changes to BMDMAState which removed pci_dev
field on the way.
- cmd646 pci_from_bm() expects bm->unit value to
correspond with bm data being passed to callback
as opaque pointer. This breaks when write to dma
control register of second channel happens when no
dma operation is in progress, so bm->unit is zero
for second channel, and pci_from_bm() returns garbage
pointer. Crash happens shortly after that while
dereferencing that pointer.
v0->v1: cleaned up dead code from pci_from_bm.
Signed-off-by: Igor V. Kovalenko <igor.v.kovalenko@gmail.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Problem: x86 systems could not survive a few system_resets.
Clear most of IDE state when reset. Implement the missing reset handlers.
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
It is used everywhere as uint8_t except in one place. Cast to uint16_t
in that place
Signed-off-by: Juan Quintela <quintela@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This allows the ide bus being initialized without drives attached
and the drives being attached and initialization later on as
separate step.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
These variables are per bus, not per drive. Lets move them and
cleanup things a bit. And fix the cmd migration bug for real.
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Christoph Hellwig
Gerd Hoffmann
Igor V. Kovalenko
Kevin Wolf
Blue Swirl
Juan Quintela