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  1. 08 4月, 2009 1 次提交
  3. 06 4月, 2009 2 次提交
    • A
      Fix the build for --disable-aio · 8185d2c9
      由 aliguori 提交于 
      This was reported by malc.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6993 c046a42c-6fe2-441c-8c8c-71466251a162
      8185d2c9
    • A
      Add host_device support to qemu-img. (Nolan Leake) · 93c65b47
      由 aliguori 提交于 
      This patch allows the use a host_device as the destination for "qemu-img
convert".

I added a ->bdrv_create function host_device.  It merely verifies that
the device exists and is large enough.

A check is needed in the qemu-img convert loop to ensure that we write
out all 0 sectors to the host_device.  Otherwise they end up with stale
garbage where all zero sectors were expected.

I also made the check against bdrv_is_allocated enabled for everything
_except_ host devices, since there is no point in making the block
backend write a bunch of zeros just so that we can memcmp them
immediately afterwards.  Host devices can't benefit from this because
there is no way to differentiate between a sector being unallocated
because it was never written, or because it was written with all zeros
and then made a trip through qemu-img convert.

Finally, there is an unrelated fix for a typo in the error message
printed if the destination device does not support ->bdrv_create.

Signed-off-by: Nolan Leake <nolan <at> sigbus.net>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6978 c046a42c-6fe2-441c-8c8c-71466251a162
      93c65b47
  5. 31 3月, 2009 1 次提交
  7. 29 3月, 2009 1 次提交
    • A
      new scsi-generic abstraction, use SG_IO (Christoph Hellwig) · 221f715d
      由 aliguori 提交于 
      Okay, I started looking into how to handle scsi-generic I/O in the
new world order.

I think the best is to use the SG_IO ioctl instead of the read/write
interface as that allows us to support scsi passthrough on disk/cdrom
devices, too.  See Hannes patch on the kvm list from August for an
example.

Now that we always do ioctls we don't need another abstraction than
bdrv_ioctl for the synchronous requests for now, and for asynchronous
requests I've added a aio_ioctl abstraction keeping it simple.

Long-term we might want to move the ops to a higher-level abstraction
and let the low-level code fill out the request header, but I'm lazy
enough to leave that to the people trying to support scsi-passthrough
on a non-Linux OS.

Tested lightly by issuing various sg_ commands from sg3-utils in a guest
to a host CDROM device.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6895 c046a42c-6fe2-441c-8c8c-71466251a162
      221f715d
  9. 28 3月, 2009 1 次提交
    • B
      FreeBSD host physical cdrom fixes · 9f23011a
      由 blueswir1 提交于 
      This improves physical cdrom support on FreeBSD hosts to be almost as
good as on Linux, with the only notable exception that you still need to
either have the guest itself eject the disc if you want to take it
out/change it, or do a change command in the monitor after taking out
a disc in case a guest cannot eject it itself - otherwise the guest may
continue using state (like size) of the old disc.
Signed-off-by: NJuergen Lock <nox@jelal.kn-bremen.de>


git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6888 c046a42c-6fe2-441c-8c8c-71466251a162
      9f23011a
  11. 13 3月, 2009 3 次提交
  13. 08 3月, 2009 3 次提交
  15. 27 2月, 2009 1 次提交
  17. 06 2月, 2009 1 次提交
  19. 30 1月, 2009 1 次提交
  21. 24 1月, 2009 1 次提交
  23. 17 1月, 2009 1 次提交
  25. 16 1月, 2009 3 次提交
  27. 13 12月, 2008 1 次提交
    • A
      Replace posix-aio with custom thread pool · 3c529d93
      由 aliguori 提交于 
      glibc implements posix-aio as a thread pool and imposes a number of limitations.

1) it limits one request per-file descriptor.  we hack around this by dup()'ing
file descriptors which is hideously ugly

2) it's impossible to add new interfaces and we need a vectored read/write
operation to properly support a zero-copy API.

What has been suggested to me by glibc folks, is to implement whatever new
interfaces we want and then it can eventually be proposed for standardization.
This requires that we implement our own posix-aio implementation though.

This patch implements posix-aio using pthreads.  It immediately eliminates the
need for fd pooling.

It performs at least as well as the current posix-aio code (in some
circumstances, even better).
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5996 c046a42c-6fe2-441c-8c8c-71466251a162
      3c529d93
  29. 14 11月, 2008 1 次提交
  31. 15 10月, 2008 2 次提交
  33. 14 10月, 2008 1 次提交
    • A
      Expand cache= option and use write-through caching by default · 9f7965c7
      由 aliguori 提交于 
      This patch changes the cache= option to accept none, writeback, or writethough
to control the host page cache behavior.  By default, writethrough caching is
now used which internally is implemented by using O_DSYNC to open the disk
images.  When using -snapshot, writeback is used by default since data integrity
it not at all an issue.

cache=none has the same behavior as cache=off previously.  The later syntax is
still supported by now deprecated.  I also cleaned up the O_DIRECT
implementation to avoid many of the #ifdefs.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5485 c046a42c-6fe2-441c-8c8c-71466251a162
      9f7965c7
  35. 09 10月, 2008 1 次提交
    • A
      Fix IO performance regression in sparc · 9e472e10
      由 aliguori 提交于 
      Replace signalfd with signal handler/pipe.  There is no way to interrupt
the CPU execution loop when a file descriptor becomes readable.  This
results in a large performance regression in sparc emulation during
bootup.
   
This patch switches us to signal handler/pipe which was originally
suggested by Ian Jackson.  The signal handler lets us interrupt the
CPU emulation loop while the write to a pipe lets us avoid the
select/signal race condition.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5451 c046a42c-6fe2-441c-8c8c-71466251a162
      9e472e10
  37. 04 10月, 2008 1 次提交
  39. 28 9月, 2008 1 次提交
    • A
      Make compatfd fallback more robust · 27463101
      由 aliguori 提交于 
      Be more friendly when signalfd() fails, and also add configure checks to detect
that syscall(SYS_signalfd) actually works.  malc pointed out that some installs
do not have /usr/include/linux headers that are in sync with the glibc headers
so why SYS_signalfd is defined, it's #defined to _NR_signalfd which is not
defined in the /usr/include/linux header.

While this is a distro bug, it doesn't hurt to do a more thorough job in
detection.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5334 c046a42c-6fe2-441c-8c8c-71466251a162
      27463101
  41. 27 9月, 2008 2 次提交
  43. 26 9月, 2008 2 次提交
    • A
      Implement an fd pool to get real AIO with posix-aio · 53538725
      由 aliguori 提交于 
      This patch implements a simple fd pool to allow many AIO requests with
posix-aio.  The result is significantly improved performance (identical to that
reported for linux-aio) for both cache=on and cache=off.

The fundamental problem with posix-aio is that it limits itself to one thread
per-file descriptor.  I don't know why this is, but this patch provides a simple
mechanism to work around this (duplicating the file descriptor).

This isn't a great solution, but it seems like a reasonable intermediate step
between posix-aio and a custom thread-pool to replace it.

Ryan Harper will be posting some performance analysis he did comparing posix-aio
with fd pooling against linux-aio.  The size of the posix-aio thread pool and
the fd pool were largely determined by him based on this analysis.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5323 c046a42c-6fe2-441c-8c8c-71466251a162
      53538725
    • A
      Fix build on FreeBSD · 997306fc
      由 aliguori 提交于 
      __GLIBC_PREREQ is defined in such a way that the ! cannot be used in front of
it on FreeBSD.  Also, -lpthread is not implied by the build and we definitely
use it for compatfd support.

While at it, I added a default initialization for posix-aio that seems to
perform well in our testing.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5322 c046a42c-6fe2-441c-8c8c-71466251a162
      997306fc
  45. 23 9月, 2008 2 次提交
    • A
      Relax posix-aio restrictions on newer glibcs · 82889986
      由 aliguori 提交于 
      RedHat 9 shipped glibc 2.3.  Modern versions of glibc do not have the aio thread
exit issue that the comment references.  This patch adjusts the check to only
limit aio_init on glibc versions < 2.4.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5304 c046a42c-6fe2-441c-8c8c-71466251a162
      82889986
    • A
      Refactor AIO to allow multiple AIO implementations · a76bab49
      由 aliguori 提交于 
      This patch refactors the AIO layer to allow multiple AIO implementations.  It's
only possible because of the recent signalfd() patch.  

Right now, the AIO infrastructure is pretty specific to the block raw backend.
For other block devices to implement AIO, the qemu_aio_wait function must
support registration.  This patch introduces a new function,
qemu_aio_set_fd_handler, which can be used to register a file descriptor to be
called back.  qemu_aio_wait() now polls a set of file descriptors registered
with this function until one becomes readable or writable.

This patch should allow the implementation of alternative AIO backends (via a
thread pool or linux-aio) and AIO backends in non-traditional block devices
(like NBD).
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5297 c046a42c-6fe2-441c-8c8c-71466251a162
      a76bab49
  47. 22 9月, 2008 1 次提交
  49. 16 9月, 2008 2 次提交
  51. 15 9月, 2008 1 次提交
    • A
      Use common objects for qemu-img and qemu-nbd · 03ff3ca3
      由 aliguori 提交于 
      Right now, we sprinkle #if defined(QEMU_IMG) && defined(QEMU_NBD) all over the
code.  It's ugly and causes us to have to build multiple object files for
linking against qemu and the tools.

This patch introduces a new file, qemu-tool.c which contains enough for
qemu-img, qemu-nbd, and QEMU to all share the same objects.

This also required getting qemu-nbd to be a bit more Windows friendly.  I also
changed the Windows block-raw to use normal IO instead of overlapping IO since
we don't actually do AIO yet on Windows.  I changed the various #if 0's to
 #if WIN32_AIO to make it easier for someone to eventually fix AIO on Windows.

After this patch, there are no longer any #ifdef's related to qemu-img and
qemu-nbd.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5226 c046a42c-6fe2-441c-8c8c-71466251a162
      03ff3ca3
  53. 12 9月, 2008 1 次提交
  55. 11 9月, 2008 1 次提交