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  1. 11 9月, 2009 2 次提交
    • C
      block: add enable_write_cache flag · e900a7b7
      由 Christoph Hellwig 提交于 
      Add a enable_write_cache flag in the block driver state, and use it to
decide if we claim to have a volatile write cache that needs controlled
flushing from the guest.  The flag is off if cache=writethrough is
defined because O_DSYNC guarantees that every write goes to stable
storage, and it is on for cache=none and cache=writeback.

Both scsi-disk and ide now use the new flage, changing from their
defaults of always off (ide) or always on (scsi-disk).
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      e900a7b7
    • K
      Add bdrv_aio_multiwrite · 40b4f539
      由 Kevin Wolf 提交于 
      One performance problem of qcow2 during the initial image growth are
sequential writes that are not cluster aligned. In this case, when a first
requests requires to allocate a new cluster but writes only to the first
couple of sectors in that cluster, the rest of the cluster is zeroed - just
to be overwritten by the following second request that fills up the cluster.

Let's try to merge sequential write requests to the same cluster, so we can
avoid to write the zero padding to the disk in the first place.

As a nice side effect, also other formats take advantage of dealing with less
and larger requests.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      40b4f539
  3. 28 8月, 2009 1 次提交
    • K
      qcow2: Metadata preallocation · a35e1c17
      由 Kevin Wolf 提交于 
      This introduces a qemu-img create option for qcow2 which allows the metadata to
be preallocated, i.e. clusters are reserved in the refcount table and L1/L2
tables, but no data is written to them. Metadata is quite small, so this
happens in almost no time.

Especially with qcow2 on virtio this helps to gain a bit of performance during
the initial writes. However, as soon as create a snapshot, we're back to the
normal slow speed, obviously. So this isn't the real fix, but kind of a cheat
while we're still having trouble with qcow2 on virtio.

Note that the option is disabled by default and needs to be specified
explicitly using qemu-img create -f qcow2 -o preallocation=metadata.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
      a35e1c17
  5. 16 7月, 2009 1 次提交
  7. 15 6月, 2009 1 次提交
    • C
      block: add bdrv_probe_device method · 508c7cb3
      由 Christoph Hellwig 提交于 
      Add a bdrv_probe_device method to all BlockDriver instances implementing
host devices to move matching of host device types into the actual drivers.
For now we keep exacly the old matching behaviour based on the devices names,
although we really should have better detetion methods based on device
information in the future.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
      508c7cb3
  9. 27 5月, 2009 1 次提交
  11. 22 5月, 2009 2 次提交
  13. 23 4月, 2009 1 次提交
    • A
      implement qemu_blockalign (Stefano Stabellini) · e268ca52
      由 aliguori 提交于 
      this patch adds a buffer_alignment field to BlockDriverState and
implements a qemu_blockalign function that uses that field to allocate a
memory aligned buffer to be used by the block driver.
buffer_alignment is initialized to 512 but each block driver can set
a different value (at the moment none of them do).
This patch modifies ide.c, block-qcow.c, block-qcow2.c and block.c to
use qemu_blockalign instead of qemu_memalign.
There is only one place left that still uses qemu_memalign to allocate
buffers used by block drivers that is posix-aio-compat:handle_aiocb_rw
because it is not possible to get the BlockDriverState from that
function. However I think it is not important because posix-aio-compat
already deals with driver specific code so it is supposed to know its
own needs.
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7229 c046a42c-6fe2-441c-8c8c-71466251a162
      e268ca52
  15. 22 4月, 2009 1 次提交
  17. 08 4月, 2009 1 次提交
  19. 06 4月, 2009 1 次提交
  21. 29 3月, 2009 2 次提交
  23. 21 3月, 2009 1 次提交
  25. 13 3月, 2009 2 次提交
  27. 06 3月, 2009 1 次提交
    • A
      monitor: Rework early disk password inquiry (Jan Kiszka) · c0f4ce77
      由 aliguori 提交于 
      Reading the passwords for encrypted hard disks during early startup is
broken (I guess for quiet a while now):
 - No monitor terminal is ready for input at this point
 - Forcing all mux'ed terminals into monitor mode can confuse other
   users of that channels

To overcome these issues and to lay the ground for a clean decoupling of
monitor terminals, this patch changes the initial password inquiry as
follows:
 - Prevent autostart if there is some encrypted disk
 - Once the user tries to resume the VM, prompt for all missing
   passwords
 - Only resume if all passwords were accepted
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6707 c046a42c-6fe2-441c-8c8c-71466251a162
      c0f4ce77
  29. 04 3月, 2009 1 次提交
    • A
      Fix CVE-2008-0928 - insufficient block device address range checking (Anthony Liguori) · 71d0770c
      由 aliguori 提交于 
      Introduce a growable flag that's set by bdrv_file_open().  Block devices should
never be growable, only files that are being used by block devices.

I went through Fabrice's early comments about the patch that was first applied.
While I disagree with that patch, I also disagree with Fabrice's suggestion.

There's no good reason to do the checks in the block drivers themselves.  It
just increases the possibility that this bug could show up again.  Since we're
calling bdrv_getlength() to determine the length, we're giving the block drivers
a chance to chime in and let us know what range is valid.

Basically, this patch makes the BlockDriver API guarantee that all requests are
within 0..bdrv_getlength() which to me seems like a Good Thing.

What do others think?
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6677 c046a42c-6fe2-441c-8c8c-71466251a162
      71d0770c
  31. 11 2月, 2009 1 次提交
  33. 09 11月, 2008 1 次提交
  35. 18 9月, 2008 1 次提交
  37. 12 3月, 2008 2 次提交
  39. 25 12月, 2007 1 次提交
  41. 02 12月, 2007 1 次提交
  43. 11 11月, 2007 1 次提交
  45. 17 9月, 2007 3 次提交
  47. 19 8月, 2006 1 次提交
  49. 07 8月, 2006 1 次提交
  51. 06 8月, 2006 2 次提交
  53. 02 8月, 2006 1 次提交
  55. 04 6月, 2006 1 次提交
  57. 19 12月, 2005 1 次提交
  59. 16 11月, 2004 1 次提交
  61. 19 9月, 2004 1 次提交
  63. 02 8月, 2004 1 次提交