Reads and writes to the underlying file can also occur with the simple
non-vectored I/O interfaces.
Acked-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
vdi.c really works as if it implemented bdrv_read and bdrv_write. However,
because only vector I/O is supported by the asynchronous callbacks, it
went through extra pain to bounce-buffer the I/O. This can be handled
by the block layer now that the format is coroutine-based.
Acked-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Most of the AIOCB really holds local variables that need to persist
across callback invocation. It can go away now.
Acked-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Now inline the former AIO callbacks into vdi_co_readv and vdi_co_writev.
While many cleanups are possible, the code now really looks synchronous.
Acked-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The next step is to take code that only triggers after the first operation,
and move it at the end of vdi_aio_read_cb and vdi_aio_write_cb.
Acked-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Even a basic conversion changing the bdrv_aio_readv/bdrv_aio_writev calls
to bdrv_co_readv/bdrv_co_writev, and callbacks to goto statements can
eliminate a lot of code. This is because error handling is simplified
and indirections through bottom halves can go away.
After this patch, I/O to the underlying file already happens via
coroutines, but the code still looks a lot like if asynchronous I/O was
being used.
Acked-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The new block was filled with zero when it was allocated by g_malloc0,
but when it was reused later and only partially used, data from the
previously allocated block were still present and written to the new
block.
This caused the problems reported by bug #919242
(https://bugs.launchpad.net/qemu/+bug/919242).
Now the unused parts of the new block which are before and after the data
are always filled with zero, so it is no longer necessary to zero the whole
block with g_malloc0.
I also updated the copyright comment.
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Initially done with the following semantic patch:
@ rule1 @
expression E;
statement S;
@@
E = qemu_aio_get (...);
(
- if (E == NULL) { ... }
|
- if (E)
{ <... S ...> }
)
which however missed occurrences in linux-aio.c and posix-aio-compat.c.
Those were done by hand.
The change in vdi_aio_setup's caller was also done by hand.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Initially done with the following semantic patch:
@ rule1 @
expression E;
statement S;
@@
E =
(
bdrv_aio_readv
| bdrv_aio_writev
| bdrv_aio_flush
| bdrv_aio_discard
| bdrv_aio_ioctl
)
(...);
(
- if (E == NULL) { ... }
|
- if (E)
{ <... S ...> }
)
which however missed the occurrence in block/blkverify.c
(as it should have done), and left behind some unused
variables.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
It is trivial to switch from the synchronous .bdrv_is_allocated()
interface to .bdrv_co_is_allocated() since vdi_is_allocated() does not
block.
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
vdi caches the block map. For migration to work, it would have to be
invalidated. Block migration for now.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
There are two different types of flush that you can do: Flushing one level up
to the OS (i.e. writing data to the host page cache) or flushing it all the way
down to the disk. The existing functions flush to the disk, reflect this in the
function name.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
An entry in the VDI block map will hold an offset to the actual block if
the block is allocated, or one of two specially-interpreted values if
not allocated. Using VirtualBox terminology, value VDI_IMAGE_BLOCK_FREE
(0xffffffff) represents a never-allocated block (semantically arbitrary
content). VDI_IMAGE_BLOCK_ZERO (0xfffffffe) represents a "discarded"
block (semantically zero-filled). block/vdi knows only about
VDI_IMAGE_BLOCK_FREE. Teach it about VDI_IMAGE_BLOCK_ZERO.
Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Since coroutine operation is now mandatory, convert all bdrv_flush
implementations to coroutines. For qcow2, this means taking the lock.
Other implementations are simpler and just forward bdrv_flush to the
underlying protocol, so they can avoid the lock.
The bdrv_flush callback is then unused and can be eliminated.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
bdrv_aio_* must not call the callback before returning to its caller. In vdi,
this could happen in some error cases. This starts the real requests processing
in a BH to avoid this situation.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
When not specifying a cluster size on the command line, qemu-img printed
a cluster size of 0:
Formatting '/tmp/test.qcow2', fmt=qcow2 size=67108864
encryption=off cluster_size=0
This patch adds the default cluster size to the QEMUOptionParameter list, so
that it displays the default value that is used.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
This patch is similar to 171e3d6b99
which fixed qcow2:
Returning -EIO is far from optimal, but at least it's an error code.
Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Error report from cppcheck:
block/vdi.c:122: error: Using sizeof for array given as function argument returns the size of pointer.
block/vdi.c:128: error: Using sizeof for array given as function argument returns the size of pointer.
Fix both by setting the correct size.
The buggy code is only used when QEMU is build without uuid support.
The bug is not critical, so there is no urgent need to apply it to
old versions of QEMU.
Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
All drivers use bs->file instead of s->hd for quite a while now, so it's time
to remove s->hd.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
This changes bdrv_flush to return 0 on success and -errno in case of failure.
It's a requirement for implementing proper error handle in users of bdrv_flush.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
This distinguishes between harmless leaks and real corruption. Hopefully users
better understand what qemu-img check wants to tell them.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The fix is based on a patch from Kevin Wolf. Here his comment:
"The number of blocks needs to be rounded up to cover all of the virtual hard
disk. Without this fix, we can't even open our own images if their size is not
a multiple of the block size."
While Kevin's patch addressed vdi_create, my modification also fixes
vdi_open which now accepts images with odd disk sizes.
v3:
Don't allow reading of disk images with too large disk sizes.
Neither VBoxManage nor old versions of qemu-img read such images.
This change requires rounding of odd disk sizes before we do the checks.
Cc: Kevin Wolf <kwolf@redhat.com>
Cc: François Revol <revol@free.fr>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Even it is not very useful, users may create images of size 0.
Without the special option CONFIG_ZERO_MALLOC, qemu_mallocz
aborts execution when it is told to allocate 0 bytes,
so avoid this kind of call.
Cc: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Format drivers shouldn't need to bother with things like file names, but rather
just get an open BlockDriverState for the underlying protocol. This patch
introduces this behaviour for bdrv_open implementation. For protocols which
need to access the filename to open their file/device/connection/... a new
callback bdrv_file_open is introduced which doesn't get an underlying file
opened.
For now, also some of the more obscure formats use bdrv_file_open because they
open() the file themselves instead of using the block.c functions. They need to
be fixed in later patches.
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
The disk image I created from my old laptop disk with VBoxManage
internalcommand converthd obviously was not a multiple of 1MB as when
created from scratch. This fixes QEMU refusing it. We still require the
size to be a multiple of sector size though.
It then boots correctly.
Allow opening VDI images with size not multiple of 1MB (as when converted from a raw disk).
Signed-off-by: François Revol <revol@free.fr>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
If available, the Universally Unique Identifier library
is used by the vdi block driver.
Other parts of QEMU (vl.c) could also use it.
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
* The code for option '-static' was wrong, so image creation
always created static images.
* Static images created with qemu-img did not set header entry
blocks_allocated.
* The size of the block map must be rounded to the next multiple
of SECTOR_SIZE, otherwise the block map is only read partially
for block map sizes which are not a multiple of SECTOR_SIZE.
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This is a new block driver written from scratch
to support the VDI format in QEMU.
VDI is the native format used by Innotek / SUN VirtualBox.
Latest changes:
* stripped down version
(code for synchronous operations and experimental code removed)
* don't open VDI snapshot images (with uuid_link or uuid_parent)
* modified vdi_aio_cancel
Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Message-Id:
