The host part of a block device can be deleted with in progress
block migration.
To fix this, add a reference count to DriveInfo, freeing resources
on last reference.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
CC: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Watch this:
(qemu) drive_add 0 if=none
(qemu) info block
none0: type=hd removable=0 [not inserted]
(qemu) drive_del none0
Segmentation fault (core dumped)
add_init_drive() is confused about drive_init()'s failure modes, and
cleans up when it shouldn't. This leaves the DriveInfo with member
opts dangling. drive_del attempts to free it, and dies.
drive_init() behaves as follows:
* If it created a drive with media, it returns its DriveInfo.
* If it created a drive without media, it clears *fatal_error and
returns NULL.
* If it couldn't create a drive, it sets *fatal_error and returns
NULL.
Of its three callers:
* drive_init_func() is correct.
* usb_msd_init() assumes drive_init() failed when it returns NULL.
This is correct only because it always passes option "file", and
"drive without media" can't happen then.
* add_init_drive() assumes drive_init() failed when it returns NULL.
This is incorrect.
Clean up drive_init() to return NULL on failure and only on failure.
Drop its parameter fatal_error.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Let the callers build the optstr. Only one wants to. All the others
become simpler, because they don't have to worry about escaping '%'.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Before, type & index were hidden in printf-like fmt, ... parameters,
which get expanded into an option string. Rather inconvenient for
uses later in this series.
New IF_DEFAULT to ask for the machine's default interface. Before,
that was done by having no option "if" in the option string.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Before commit 622b520f, index=12 meant bus=1,unit=5.
Since the commit, it means bus=0,unit=12. The drive is created, but
not the guest device. That's because the controllers we use with
if=scsi drives (lsi53c895a and esp) support only 7 units, and
scsi_bus_legacy_handle_cmdline() ignores drives with unit numbers
exceeding that limit.
Changing the mapping of index to bus, unit is a regression. Breaking
-drive invocations that used to work just makes it worse.
Revert the part of commit 622b520f that causes this, and clean up
some.
Note that the fix only affects if=scsi. You can still put more than 7
units on a SCSI bus with -device & friends.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
qdev_init_bdrv() doesn't belong into qdev.c; it's about drives, not
qdevs. Rename to drive_get_next, move to blockdev.c, drop the bogus
DeviceState argument, and return DriveInfo instead of
BlockDriverState.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Add a monitor command that allows resizing of block devices while
qemu is running. It uses the existing bdrv_truncate method already
used by qemu-img to do it's work. Compared to qemu-img the size
parsing is very simplicistic, but I think having a properly numering
object is more useful for non-humand monitor users than having
the units and relative resize parsing.
For SCSI devices the new size can be updated in Linux guests by
doing the following shell command:
echo > /sys/class/scsi_device/0:0:0:0/device/rescan
For ATA devices I don't know of a way to update the block device
size in Linux system, and for virtio-blk the next two patches
will provide an automatic update of the size when this command
is issued on the host.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The monitor command is:
snapshot_blkdev <device> [snapshot-file] [format]
Default format is qcow2. For now snapshots without a snapshot-file, eg
internal snapshots, are not supported.
Signed-off-by: Jes Sorensen <Jes.Sorensen@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The SCSI parallel interface has a limit of 8 devices, but
not the SCSI stack in general. So we should be removing the
hard-coded limit and use MAX_SCSI_DEVS instead.
And we only need to scan those devices which are allocated
by the bus.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Currently device hotplug removal code is tied to device removal via
ACPI. All pci devices that are removable via device_del() require the
guest to respond to the request. In some cases the guest may not
respond leaving the device still accessible to the guest. The management
layer doesn't currently have a reliable way to revoke access to host
resource in the presence of an uncooperative guest.
This patch implements a new monitor command, drive_del, which
provides an explicit command to revoke access to a host block device.
drive_del first quiesces the block device (qemu_aio_flush;
bdrv_flush() and bdrv_close()). This prevents further IO from being
submitted against the host device. Finally, drive_del cleans up
pointers between the drive object (host resource) and the device
object (guest resource).
Signed-off-by: Ryan Harper <ryanh@us.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Additional changes:
* Removed 'extern' from drive_add (avoids too long line).
* Removed 'extern' from other functions (makes declarations
consistent with others in same header file).
Cc: Blue Swirl <blauwirbel@gmail.com>
Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
Changing block.h or blockdev.h resulted in recompiling most objects.
Move DriveInfo typedef and BlockInterfaceType enum definitions
to qemu-common.h and rearrange blockdev.h use to decrease churn.
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
We automatically delete blockdev host parts on unplug of the guest
device. Too much magic, but we can't change that now.
The delete happens early in the guest device teardown, before the
connection to the host part is severed. Thus, the guest part's
pointer to the host part dangles for a brief time. No actual harm
comes from this, but we'll catch such dangling pointers a few commits
down the road. Clean up the dangling pointers by delaying the
automatic deletion until the guest part's pointer is gone.
Device usb-storage deliberately makes two qdev properties refer to the
same drive, because it automatically creates a second device. Again,
too much magic we can't change now. Multiple references worked okay
before, but now free_drive() dies for the second one. Zap the extra
reference.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This is the list of drives defined with drive_init(). Hide it, so it
doesn't get abused.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
That's where they belong semantically (block device host part), even
though the actions are actually executed by guest device code.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Anything that moves hundreds of lines out of vl.c can't be all bad.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
