Skip to content

Q
qemu

openeuler / qemu

通知 10
Star 0
Fork 0
Q
qemu
切换分支/标签
  1. 20 10月, 2014 2 次提交
  3. 12 9月, 2014 2 次提交
  5. 16 6月, 2014 2 次提交
  7. 04 6月, 2014 2 次提交
  9. 30 4月, 2014 1 次提交
    • K
      block: Unlink temporary files in raw-posix/win32 · 8bfea15d
      由 Kevin Wolf 提交于 
      Instead of having unlink() calls in the generic block layer, where we
aren't even guarateed to have a file name, move them to those block
drivers that are actually used and that always have a filename. Gets us
rid of some #ifdefs as well.

The patch also converts bs->is_temporary to a new BDRV_O_TEMPORARY open
flag so that it is inherited in the protocol layer and the raw-posix and
raw-win32 drivers can unlink the file.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
      8bfea15d
  11. 13 3月, 2014 1 次提交
  13. 06 3月, 2014 2 次提交
  15. 18 2月, 2014 1 次提交
  17. 25 1月, 2014 1 次提交
  19. 07 1月, 2014 1 次提交
  21. 14 11月, 2013 1 次提交
    • F
      block: Print its file name if backing file opening failed · b04b6b6e
      由 Fam Zheng 提交于 
      If backing file doesn't exist, the error message is confusing and
misleading:

    $ qemu /tmp/a.qcow2
    qemu: could not open disk image /tmp/a.qcow2: Could not open file: No
    such file or directory

But...

    $ ls /tmp/a.qcow2
    /tmp/a.qcow2

    $ qemu-img info /tmp/a.qcow2
    image: /tmp/a.qcow2
    file format: qcow2
    virtual size: 8.0G (8589934592 bytes)
    disk size: 196K
    cluster_size: 65536
    backing file: /tmp/b.qcow2

Because...

    $ ls /tmp/b.qcow2
    ls: cannot access /tmp/b.qcow2: No such file or directory

This is not intuitive. It's better to have the missing file's name in
the error message. With this patch:

    $ qemu-io -c 'read 0 512' /tmp/a.qcow2
    qemu-io: can't open device /tmp/a.qcow2: Could not open backing
    file: Could not open '/stor/vm/arch.raw': No such file or directory
    no file open, try 'help open'

Which is a little bit better.
Signed-off-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      b04b6b6e
  23. 29 10月, 2013 1 次提交
    • K
      block: Avoid unecessary drv->bdrv_getlength() calls · b94a2610
      由 Kevin Wolf 提交于 
      The block layer generally keeps the size of an image cached in
bs->total_sectors so that it doesn't have to perform expensive
operations to get the size whenever it needs it.

This doesn't work however when using a backend that can change its size
without qemu being aware of it, i.e. passthrough of removable media like
CD-ROMs or floppy disks. For this reason, the caching is disabled when a
removable device is used.

It is obvious that checking whether the _guest_ device has removable
media isn't the right thing to do when we want to know whether the size
of the host backend can change. To make things worse, non-top-level
BlockDriverStates never have any device attached, which makes qemu
assume they are removable, so drv->bdrv_getlength() is always called on
the protocol layer. In the case of raw-posix, this causes unnecessary
lseek() system calls, which turned out to be rather expensive.

This patch completely changes the logic and disables bs->total_sectors
caching only for certain block driver types, for which a size change is
expected: host_cdrom and host_floppy on POSIX, host_device on win32; also
the raw format in case it sits on top of one of these protocols, but in
the common case the nested bdrv_getlength() call on the protocol driver
will use the cache again and avoid an expensive drv->bdrv_getlength()
call.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
      b94a2610
  25. 17 10月, 2013 1 次提交
  27. 11 10月, 2013 1 次提交
  29. 25 9月, 2013 1 次提交
  31. 12 9月, 2013 3 次提交
  33. 06 9月, 2013 1 次提交
  35. 28 6月, 2013 1 次提交
    • P
      block: change default of .has_zero_init to 0 · 3ac21627
      由 Peter Lieven 提交于 
      .has_zero_init defaults to 1 for all formats and protocols.

this is a dangerous default since this means that all
new added drivers need to manually overwrite it to 0 if
they do not ensure that a device is zero initialized
after bdrv_create().

if a driver needs to explicitly set this value to
1 its easier to verify the correctness in the review process.

during review of the existing drivers it turned out
that ssh and gluster had a wrong default of 1.
both protocols support host_devices as backend
which are not by default zero initialized. this
wrong assumption will lead to possible corruption
if qemu-img convert is used to write to such a backend.

vpc and vmdk also defaulted to 1 altough they support
fixed respectively flat extends. this has to be addresses
in separate patches. both formats as well as the mentioned
ssh and gluster are turned to the default of 0 with this
patch for safety.

a similar problem with the wrong default existed for
iscsi most likely because the driver developer did
oversee the default value of 1.
Signed-off-by: NPeter Lieven <pl@kamp.de>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
      3ac21627
  37. 22 4月, 2013 2 次提交
  39. 25 3月, 2013 1 次提交
  41. 15 3月, 2013 1 次提交
    • S
      threadpool: drop global thread pool · c4d9d196
      由 Stefan Hajnoczi 提交于 
      Now that each AioContext has a ThreadPool and the main loop AioContext
can be fetched with bdrv_get_aio_context(), we can eliminate the concept
of a global thread pool from thread-pool.c.

The submit functions must take a ThreadPool* argument.

block/raw-posix.c and block/raw-win32.c use
aio_get_thread_pool(bdrv_get_aio_context(bs)) to fetch the main loop's
ThreadPool.

tests/test-thread-pool.c must be updated to reflect the new
thread_pool_submit() function prototypes.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
      c4d9d196
  43. 02 1月, 2013 1 次提交
  45. 19 12月, 2012 2 次提交
  47. 11 12月, 2012 1 次提交
  49. 31 10月, 2012 2 次提交
  51. 24 9月, 2012 2 次提交
  53. 15 8月, 2012 2 次提交
  55. 11 11月, 2011 1 次提交