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: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7229 c046a42c-6fe2-441c-8c8c-71466251a162
Make all AIO requests vectored and defer linearization until the actual
I/O thread. This prepares for using native preadv/pwritev.
Also enables asynchronous direct I/O by handling that case in the I/O thread.
Qcow and qcow2 propably want to be adopted to directly deal with multi-segment
requests, but that can be implemented later.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7020 c046a42c-6fe2-441c-8c8c-71466251a162
Always use the vectored APIs to reduce code churn once we switch the BlockDriver
API to be vectored.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@7019 c046a42c-6fe2-441c-8c8c-71466251a162
Consistently use the C99 named initializer format for the BlockDriver
methods to make the method table more readable and more easily
extensible.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6768 c046a42c-6fe2-441c-8c8c-71466251a162
Revert r4673, the removed dead code wasn't dead in fact.
Additionally, change the misleading else which tricks the reader into
believing that allocate is a boolean to else if (allocate == 2).
Signed-off-by: Kevin Wolf <kwolf@suse.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@6244 c046a42c-6fe2-441c-8c8c-71466251a162
Qemu 0.9.1 and earlier does not perform range checks for block device
read or write requests, which allows guest host users with root
privileges to access arbitrary memory and escape the virtual machine.
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4037 c046a42c-6fe2-441c-8c8c-71466251a162
Remove QEMU_TOOL. Replace with QEMU_IMG and NEED_CPU_H.
Avoid linking qemu-img against whole system emulatior.
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@3578 c046a42c-6fe2-441c-8c8c-71466251a162
