The alignment field is now set to the value that is promised to the
guest, rather than required by the host. The next patches will make
QEMU aware of the host-provided values, so make this clear.
The alignment is also not about memory buffers, but about the sectors on
the disk, change the documentation of the field.
At this point, the field is set by the device emulation, but completely
ignored by the block layer.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Wenchao Xia <xiawenc@linux.vnet.ibm.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Benoit Canet <benoit@irqsave.net>
Some emulated disk operations (MODE SELECT, UNMAP, WRITE SAME)
can trigger asynchronous I/Os. Provide the cancel_io callback
to ensure that AIOCBs are properly cleaned up.
Signed-off-by: Eric Farman <farman@linux.vnet.ibm.com>
Cc: qemu-stable@nongnu.org
[Tweak commit message. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Linux prefers WRITE SAME to UNMAP if the limits are zero, and WRITE
SAME does not discard anything unless the device can guarantee that
the resulting block is zero.
Setting the maximum unmap block and descriptor counts to non-zero
makes Linux choose UNMAP and fixes thin provisioning on glusterfs.
While the maximum unmap block count can have some effect on performance,
the (suggested) maximum number of descriptors is not particularly
important so I didn't add a customization option. SCSI drivers are
used to online firmware updates so I'm not yet adding versioning support
for SCSI, but we're probably getting close to the point when it's worth
thinking about it.
Reported-by: Bharata B Rao <bharata@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
VERIFY emulation was completely botched (and remained botched through
all the refactorings). The command must be emulated both in check-medium
mode (BYTCHK=00, which we implement by doing nothing) and in check-bytes
mode (which we do not implement yet). Unlike WRITE AND VERIFY (which we
treat simply as WRITE with FUA bit set), VERIFY cannot be handled like
READ. In fact the device is _receiving_ data for VERIFY, not _sending_
it like READ.
Cc: qemu-stable@nongnu.org
Tested-by: Hervé Poussineau <hpoussin@reactos.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Fetch the data to be written from the input buffer. If it is all zeroes,
we can use the write_zeroes call (possibly with the new MAY_UNMAP flag).
Otherwise, do as many write cycles as needed, writing 512k at a time.
Strictly speaking, this is still incorrect because a zero cluster should
only be written if the MAY_UNMAP flag is set. But this is a bug in qcow2
and the other formats, not in the SCSI code.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Since we report ANC_SUP==0 in VPD page B2h, we need to return
an error (ILLEGAL REQUEST/INVALID FIELD IN CDB) for all WRITE SAME
requests with ANCHOR==1.
Inspired by a similar patch to the LIO in-kernel target.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This is the same that is already done for WRITE SAME.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
This patch adds a new SCSI_DISK_F_NO_REMOVABLE_DEVOPS feature. By this
feature we can set that the scsi-block (scsi pass-through) device will still
be removable from the guest side, but from monitor it cannot be removed.
Cc: qemu-stable@nongnu.org
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Tray statuses should be also reset. Some guests may lock the tray and
right after resetting the guest it should be unlocked and closed. This
is done on power-on, reset and resume from suspend/hibernate on bare-metal.
This fix is already committed for IDE CD.
Check the commit a7f3d65b65.
Test results on bare-metal:
- on reset/power-on the CD-ROM tray is closed even before the monitor
is turned on
- on resume from suspend/hibernate the tray is also closed before
the monitor is turned on
From test results it seems that this behavior is OS and probably BIOS
independent.
Cc: qemu-stable@nongnu.org
Signed-off-by: Pavel Hrdina <phrdina@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
A verify command is not an actual read (we do not implement
compare mode) and thus does not have an AIOCB attached. Do
not crash in scsi_dma_complete.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>